Arango 1995 Localized Alteraciones in Pre- And Postsynaptic Serotonine

8/14/2019 Arango 1995 Localized Alteraciones in Pre- And Postsynaptic Serotonine

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122 V. Arango e t al. /B ra in Research 688 (1995) 121-133T h e s e c o n d d o m a i n o f s t u d y i n v o l v e s a s s e s s m e n t o f

se ro ton in r e c e p to r s . Se ro ton in r e c e p to r s w e re o r ig ina l lyc l a ss i f ie d a s 5 -H T 1 a nd 5 -H T 2 [65] . Subtypes of 5-HT~re c e p to r s , na me ly 5 -H TIA a nd 5 -H TI~ , w e re soon p ro -pose d [32 ,64 ] . M ore r e c e n t ly , o the r 5 -H T 1 re c e p to r sub -type s a s w e l l a s 5 -H T3 [14 ,40 ] , 5 -H T4 [28] and other[15 ,75 ] r e c e p to r sub type s ha ve be e n re po r t e d . W e p re v i -o u s l y f o u n d t h a t 5 - H T2 sites, as labeled by 125I-lysergicac id d ie thylamide ([125I]LSD) [1] or [3H]spiroper idol [54] ,a re i nc re a se d in t he b ra in o f su i c ide v i c t ims , c ompa re d tocontro ls . We a lso found tha t 5-HT~ si tes , as labe led by[3H ]5 -H T , a re una l t e re d [54 ]. T he 5 -H T1 A re c e p to r , apos t syna p t i c se ro ton in r e c e p to r i n t he c e re b ra l c o r t e x , i s o fpa r t i c u l a r i n t e re s t be c a use o f r e c e n t r e po r t s t ha t 5 -H T~Abinding is increased in su ic ide v ic t ims [38,56] , as wel l asi t s poss ib l e i nvo lve me n t i n a nx ie ty a nd a f fe c t ive d i so rde r sa s sugge s t e d by the a nx io ly t i c a nd a n t ide p re ssa n t p rope r -t ies of par t ia l 5-HTIA agonists [74] .

A n inde x o f t he se ro ton in ne rve t e rmina l i n t e g r i t y ma ybe ob ta ine d f rom b ind ing s tud ie s o f t he se ro ton in t r a ns -po r t e r , w h ic h ma y be a be t t e r i nd i c a to r o f t he a bno rma l i -t i e s a ssoc i a te d w i th su i c ide tha n c o r t i c a l l e ve l s o f se ro ton ino r 5 -H IA A [43 ] . N o t a l l s t ud i e s a g re e a s t o w he the rb ind ing to t he se ro ton in t r a nspo r t e r on ne rve t e rmina l s i sr e duc e d in c o r t i c a l r e g ions o f su i c ide v i c t ims [2 ]. H ow e ve r ,mos t s tud ie s o f t he se ro ton in t r a nspo r t e r i n su i c ide v i c timsha ve e mp loye d [3H ] imip ra mine a s t he l i ga nd , w h ic h ha sbe e n show n to b ind to bo th h igh - a nd low -a f f in i ty s i t e s[19 ,37 ] , a nd to nons e ro tone rg i c r e c e p to r s suc h a s m us-car in ic chol inergic s i tes [24] . Only the h igh-aff in i ty s i terepresents b inding to the se rotonin t ransporte r [24] . Inc on t ra s t, [3H ]pa roxe t ine [34 ] a nd [3H ]c y a no imip ra mine( [3H ]C N -IMI) b ind to a s ing le c l a ss o f b ind ing s i t e[27,35,42] , the h igh-aff in i ty s i te . Studies of [3H]imipra-mine in homoge na te s f rom f ron ta l c o r t e x a re d iv ide d intha t a bou t ha l f found a de c re a se i n t he su i c ide g roup a ndthe r e ma inde r found no c ha nge ( se e [2 ] fo r r e v i e w ) . Th re es tud ie s ha ve u se d [3H ]pa roxe t ine a s t he l iga nd a nd tw o o fthose [45 ,46 ] r e po r t e d no c ha nge s i n t he f ron ta l c o r t e x(B rodma nn a re a 10 ) o f de p re sse d su i c ide v i c t ims c om-pa re d to c on t ro l s . The th i rd s tudy [36 ] w a s f rom ou rl a bo ra to ry a nd found a 40% re duc t ion in d rug - f re e su i c idev ic t ims .

The a bove s tud ie s sugge s t t ha t t he re a re se ro ton in r e -ceptor a l te ra t ions in the bra in of su ic ide v ic t ims. Mosts tud ie s e xa mine d homoge na te s f rom p re f ron ta l c o r t e x a ndp rov ide l i t t l e a na tomic a l i n fo rma t ion a s t o t he e x t e n t a ndloc a l i z a t ion o f se ro ton in r e c e p to r c ha nge s i n su i c ide . W ethe re fo re sough t t o l oc a l i z e w he re , w i th in t he p re f ron ta lc o r t e x o f su i c ide v i c t ims , p re syna p t i c ( se ro ton in t r a ns -po r t e r ) a nd pos t syna p t i c (5 -H T1A ) se ro ton in r e c e p to rc ha nge s a re p re se n t , a nd w he the r t he se c ha nge s i n p re -a nd pos t syna p t i c b ind ing s i t e s a re c o loc a l i z e d .

W e use d the se l e c t ive l i ga nds [3H ]8 -hyd roxy -2 - (d i -n -p r o p y l - a m i n o ) - t e t r a l i n ( [ 3 H ] 8 - O H - D P A T ) [ 3 2 ] a n d[3H ]C N -IMI [42 ] t o pe r fo rm qua n t i t a t i ve r e c e p to r a u to -

ra d iog ra phy o f 5 -H TIA a nd se ro ton in t r a nspo r t e r b ind ing ,respec t ive ly , in adjacent sec t ions of t i ssue taken from thep re f ron ta l c o r t e x o f su i c ide v i c t ims a nd ma tc he d c on t ro l s .Th i s a pp roa c h a l low e d ma pp ing o f b ind ing s i t es a c rossmu l t ip l e r e g ions o f t he p re f ron ta l c o r t e x a nd the c ompa r i -son o f t he p re c i se l oc a l i z a t ion o f c ha nge s a ssoc i a t e d w i thsuic ide .

2 M a t e r i a l s a n d m e t h o d s

Tissue w a s p rov ide d by loc a l C orone r o r Me d ic a l Ex -a mine r o f f i c e s i n a c c o rda nc e w i th c i t y o r c oun ty r e gu la -t i ons a nd the p ro toc o l w a s a pp rove d by the In s t i t u t i ona lR e v ie w B oa rd fo r B iome d ic a l R e se a rc h . A n e sse n t i a l a s -pe c t o f t he me thods invo lve d pe r fo rming the a ssa ys fo r t hetwo binding si te popula t ions (5-HT)A and serotonin t rans-po r t e r ) on a d j a c e n t t i s sue se c t ions c u t f rom the sa me b loc ko f t i s sue f rom e a c h c a se , i n o rde r t o pe rmi t ma x ima lc ompa ra b i l i t y fo r a sse ss ing the de g re e o f c o loc a l i z a t ion o fchanges in b inding to the two si tes .

W e e mploye d a ma tc he d -pa i r s de s ign . The c a use o fde a th w a s de t e rmine d by the C orone r o r Me d ic a l Exa m-ine r . Ea c h su i c ide c a se (n = 22 ) w a s ma tc he d w i th ac on t ro l sub je c t (n = 22 ) on the ba s is o f pos tmor t e m in t er -va l (PMI, + 5 h) , age (___5 years) , sex , season of dea th ,s ide o f b ra in a nd , w he ne v e r poss ib le , r a c e . The tw o g roup sw e re t e s t ed fo r d i f f e re nc e s i n a ge , se x a nd ra c e . The re su l tsa re de sc r ibe d be low . The b ra in sa mp le s w e re c ode d a nda ssa ye d toge the r by pe r sonne l b l ind to t he c a use o f de a th .Individua ls wi th a h istory of cerebra l t rauma, centra l ner-vous system disease , chronic a lcohol ism, i l l ic i t or thera-pe u t i c d rug u se o r A ID S w e re e xc lude d . B ody f lu id s(b lood , b i l e , a que ous humor a nd u r ine ) unde rw e n t t ox i c o -log ic a l sc re e n ing fo r c oc a ine , op i a t e s , a l c oho l a nd o the rac id ic and basic drugs.2 . 1 . C o l l e c t i o n , d i s s e c t i o n a n d s t o r a g e o f b r a i n s a m p l e s

B ra ins w e re c o l l e c t e d a nd b i se c t e d a t a u topsy . Th e r igh the misphe re s w e re c u t c o rona l ly i n to 1 .5 -c m- th i c k se c t ionsus ing a L ipsha w ma c ro tome (L ipsha w C orp . , D e t ro i t , MI) .B loc ks w e re p l a c e d on a g l a ss s l i de , imme rse d in f r e on( - 20C ) a nd s to re d a t -80C un t i l se c t ion ing . Sa mple sf rom the l e f t he misphe re w e re sa ve d fo r ne u ropa tho log ic a la nd tox ic o log ic a l ana ly se s . A f t e r a c on t ro l a nd su i c idewere matched, t i ssue was sec t ioned a t 20 /~m with a la rgeb o d y L i p s h a w c r y o t o m e ( 1 8 0 0 -N R e s e a r ch m o d e l , L i p -s h a w C o rp . , D e t r oi t , M I , - 1 4 t o - 1 8 C ) . C o r o n a l s e c -t i ons f rom the e n t i r e he mic e re b rum w e re t a ke n f rom al e ve l j u s t a n t e r io r to t he ge nu o f t he c o rpus c a l lo sum. Th i sl e ve l w a s c hose n be c a use i t c on ta in s p re f ron ta l c o r t i c a la re a s be l i e ve d to be invo lve d in h ighe r c ogn i t i ve func t ions ,a f fe c t a nd e mo t ion , a s w e l l a s i n t he t e mpora l o rga n iz a t iono f be ha v io r [30] . Se c t ions (n = 100 ) w e re c o l l e c t e d se r i a ll ya nd tha w -moun te d on to 3 5 ge l a t i n -subbe d , a c id -


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v. Arango et al. / Brain Research 688 (1995) 121-133 123c le a ne d g l a ss s l i de s . A n in t e rc a l a t i ng se t ( e ve ry 200 / z m)was sta ined for Nissl substance . Six sec t ions per bra inw e re u se d fo r e a c h re c e p to r a ssa y . Th i s c o l l e c t ion p ro toc o la l low e d fo r t he s tudy o f mu l t i p l e r e c e p to r popu la t ions i nessent ia l ly ident ica l bra in cor t ica l a reas. Tissue sec t ionsw e re de s i c c a t e d a nd s to re d in se al e d boxe s ( a t - 20 C fo r24 h , a nd -8 0 C the re a f te r ) .2.2. In Htro receptor autoradiographyAssociation / Dissociation / Competition Experiments

To ob ta in op t ima l a ssa y c on d i t i ons , a ssoc i a tion , d i s soc i -a t i on a nd c ompe t i t i on c u rve s w e re ob ta ine d ( in qua d rup l i -c a t e ) u s ing s l i de -mou n te d ra t b ra in se c t ions p r io r t o be g in -n ing the huma n e xpe r ime n t s . Se c t ions w e re w ipe d f romthe s l i de w i th f i l t e r d i sc s (W ha tma n G F/B ) a nd c oun te d ina l i qu id sc in t i l la t i on spe c t roph o tome te r (Pa c ka rd In s t ru -m e n t C o . , M e r i d e n, C T ) . B i n d i n g o f [ 3 H ] 8 - O H - D P A Tre a c he d e qu i l i b r ium in 60 min 01/,_ = 7 min) , and the bestspe c i f i c /nonspe c i f i c r a t i o w a s a c h ie ve d fo l low ing a 10min w a sh . C ompe t i t i on c u rve s w i th 12 c onc e n t ra t i ons o fse ro ton in (100 pM to 100 /xM) de t e rmin e d the IC 5o to be3 .16 nM. B ind ing o f [3H ]C N -IMI re a c he d e qu i l i b r ium a t24 h (t~/2 = 4 h ) a nd the IC 5o fo r se r t r a li ne w a s 36 nM.The op t imum w a sh t ime w a s de t e rmine d to be 60 min .General procedure

D ry se c t ions f rom one ma tc he d pa i r w e re su r rounde dw i th de n ta l w a x (Mi l e s Inc . , Sou th B e nd , IN ) a nd inc u -ba t e d w i th 8 -1 0 ml o f li ga nd in a humid i ty c ha mbe r .W a she s w e re done in la rge p l e x ig l a ss j a r s , t hus e nsu r ingthe p re se nc e o f e xc e ss bu f fe r t o r e move nonspe c i f i c b ind -ing . A l l bu f fe r s w e re i so smot i c t o p re se rve the i n t e g r i t y o fthe t i ssue . Fo l low ing the w a she s , t he s l i de s w e re d ippe d ind i s t il l e d H 2 0 (4C ) , t he ti s sue w a s d r i e d w i th c o ld , f i l t e re da i r a nd va c uum de s i c c a t e d ove rn igh t a t 4 C . D r i e d se c t ionsf rom a ma tc he d pa i r w e re a r ra nge d in X - ra y c a sse t t e sa long w i th 3H -s t a nda rds (A R C -138 , A me r i c a n R a d io l a -be l e d C he mic a l s Inc . , S t . Lou i s , MO ) a nd e xpose d to~H -se ns i t i ve f i lm (U l t ro f i lm , A me rsha m C o . , A r l ing tonH e igh t s , [L) fo r 8 a nd 20 w e e ks fo r [3H ]8 -O H -D PA T a nd[3H ]C N -IMI , r e spe c t ive ly . A t t he e nd o f t he e xposu repe r iod , t he f i lms w e re de ve lope d a c c o rd ing to t he ma nu-fa c tu re r ' s p ro toc o l (Ea s tma n K oda k C o . , R oc he s t e r , N Y ) .[ 3H]8-OH-DPA T binding

Tissue se c t ions w e re p re inc uba te d (30 min , 23C ) in170 mM Tr i s -H C 1 c on ta in ing 4 mM C a C I 2 a nd 138 m Msuc rose (pH 7 .6 ) . Inc uba t ions w e re c a r r i e d ou t i n t he sa meb u f f e r c o n t a in i n g 2 n M [ 3 H ] O H - D P A T an d 0 . 0 1 a s c o r-b i c a c id a t 21C fo r 60 m in . Pa ra l l e l i nc uba t ions c on ta in ing1 / J .M 5 -H T (oxa la t e sa l t) de f ine d nonspe c i f i c b ind ing ,w h ic h w a s le ss tha n 10 o f t o t a l b ind ing . Se r tr a l i ne (10nM) w a s a dde d to i nc uba t ions i n o rde r t o ma sk b ind ing toserotonin uptake si tes [29] . The addi t ion of se r t ra l ine a tt h is c onc e n t ra t i on (10 nM) d id no t a f fe c t b ind ing to 5 -H T]A

si tes . Sec t ions w ere w ashed for l0 ra in (2 5 ra in) inTr i s -H C l bu f fe r a t 4 C .[3H]CN-IM1 binding

Se c t ions w e re p re inc uba te d (30 ra in , 23C ) in 50 mMTr i s -H C l bu f fe r w i th 130 mM N a C I a nd 5 mM K C I (pH7 .4 ) . To ta l b ind ing w a s de t e rmine d by inc uba t ion (4 C ) inthe sa me bu f fe r c on ta in ing 0 .4 nM [3H ]C N -IM I fo r 24 h .N onspe c i f i c b ind ing w a s de f ine d by c o inc uba t ion o f a d j a -cent sec t ions wi th 1 /xM ser t ra l ine (modif ica t ion of [42]) .N onsp e c i f i c b ind ing w a s l e ss t ha n 20 . Se c t ions w e rew a she d in c o ld bu f fe r fo r 1 h (3 20 m in ) .Quantitation of autoradiograms

A uto ra d iog ra ms w e re a na lyz e d u s ing a PC -ba se d ima gea na lys i s sy s t e m ( Ima g ing R e se a rc h , Inc . , S t . C a the r ine ,Ont . , Canada) . Fi lms were d ig i t ized , shade correc ted andca l ibra ted aga inst t r i t ium standards (ARC. St . Louis , MO).H i s to log ic a l e xa mina t ion o f N i ss l -s t a ined se c t ions w a s u se din the de t e rmina t ion o f t he bounda r i e s o f c o r t i c a l l a ye r sa nd the i r c o r re spond e nc e to i sode ns i ty ba nds in t he a u to -radiograms. Brodmann areas 8 , 9 , 46 , 45 , 47 , 11 , 12 , 32a nd 24 w e re i de n t i f i e d u s ing gy ra l a nd su l c a l l a ndma rks ,c y toa rc h i t e c tu re a nd a s t a nda rd i z e d c o ron a l a t l as (R ob e r tPe r ry a nd Edw a rd B i rd , pe r sona l c ommunic a t ion ) . Ima ge sf rom se c t ions i nc uba te d in t he p re se nc e o f t he r a d io l iga nda lone ( to t a l b ind ing ) w e re a c qu i re d f i r s t . Ima ge s p roduc e df rom inc uba t ion in t he p re se nc e o f d i sp l a c e r (nonspe c i f i cb ind ing ) w e re t he n a c qu i re d a nd d ig i t a l l y sub t ra c t e d f romthe to t al b ind ing . W e thus m e a su re d spe c i f i c b ind ing , i nf m o l / m g t is s u e, f o r e a c h r e ce p t o r. M e a s u r e m e n t s o f b i n d -ing w e re t a ke n f rom e a c h o f t he i nd iv idua l i sode ns i tybands, as wel l as across the fu l l width of the cor t ica l grayma t t e r , f rom bo th the gy rus a nd su l c us . Me a su re me n t swere taken from a l l a reas ava i lable in the three resul t inga u to ra d iog ra ms pe r b ra in . Mul t ip l e r e a d ings f rom e a c hre g ion w e re a ve ra ge d . In i n s t a nc e s w he re g ra y ma t t e r w a sd i sc on t inuous , me a su re me n t s e xc lude d miss ing t i s sue .B ind ing to w h i t e ma t t e r w a s t a ke n a s t he a ve ra ge o fmu l t ip l e me a su re me n t s t h roughou t t he se c t ions . S t a nda rdsw e re c o r re c t e d da i ly fo r r a d ioa c t ive de c a y .2.3. Hig h pressure liquid chromatography (HPLC ) analy-sis of serotonin, 5-HIAA, 5-hydroxytryptophan (5-HTP)and t.-tryptophan (L-try) le~ els

A mod i f i c a t ion o f t he me thod o f K orp i a nd c o l l e a gue s[41 ] w a s u se d fo r de t e rmina t ion o f t he l e ve l s o f se ro ton in ,i t s p re c u r so r s (5 -H TP, L- t ry ) a nd p r inc ipa l me ta bo l i t e (5 -H IA A ) . T i ssue w a s son ic a t e d in 0 .1 M pe rc h lo r i c a c id( 4 C ) c o n t a in i n g N - m e t h y l - 5 - h y d r o x y t r y p t a m i n e ( N M E T ,0.1 /xM) as the in te rna l s tandard . An a l iquot of the ho-moge na te w a s u se d fo r p ro t e in a na ly s i s [49 ] , a nd there ma in ing hom oge na te w a s c e n t r i fuge d a t 10 ,000 X g (8min, 4C). Superna tants were d i lu ted 2 fo ld wi th cold 0 .1M pe rc h lo r i c a c id a nd in j e c t e d in to t he H PLC c o lumn .


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124 v . Ar ango e t al . /B r a in R es ear ch 688 1995) 12 1 -133T h e H P L C c o n s i st e d o f a W a t e r s M - 5 0 1 h i g h p re s s ur e

p u m p , a W I S P a u t o s a m p l e r , a R a i n i n D y n a m a x 5 p ~ MC 1 8 r e v e r s e - p h a s e a n a l y t i c a l a n d g u a r d c o l u m n s a n d aW a t e r s 4 6 0 e l e c t r o c h e m i c a l d e t e c t o r . T h e m o b i l e p h a s ec o n s i st e d o f 7 5 m M s o d i u m p h o s p h a t e b u f f e r (p H 3 . 0 )c o n t a i n i n g 7 . 5 % a c e t o n i t ri l e ( v / v ) , 0 . 9 m M 1 - o c t a n e s u l -f o n i c a c id a n d 5 0 / z M d i s o d i u m E D T A . T h e f lo w r a te w a s1 . 0 m l / m i n . W o r k i n g e l e ct r o d e p o t e n ti a l w a s k e p t a t+ 0 . 8 V a g a i n s t a n A g / A g C 1 r e f e r e n c e e l e c tr o d e . T y p i c a lr e t e n ti o n t i m e s ( K ) f o r 5 - H T P , 5 - H I A A , s e r o t o n i n , L - tr ya n d N M E T w e r e 5 . 9 m i n , 1 1 . 4 m i n , 2 0 . 5 m i n , 2 4 m i n a n d2 5 . 2 m i n , r e s p e c t i v e l y . A l l d a t a w e r e e x p r e s s e d a s p m o lp e r m g p r o t e i n .

D a t a w e r e a c q u i r e d a n d a n a l y z e d u s i n g a W a t e r s B a s e -l i n e 8 1 0 s o f t w a r e p a c k a g e ( D y n a m i c S o l u t i o n s , M i l l i p o r e ,M i l f o r d , M A ) . B o t h e x t e r n a l a n d i n t e r n a l s t a n d a r d s w e r eu s e d f o r q u a n t i t a t i o n a n d d a t a w e r e c a l c u l a t e d b a s e d o ns a m p l e p e a k a r e a r e l a t i v e t o i n t e r n a l s t a n d a r d p e a k a r e a .T h e s t a n d a r d c u r v e s w e r e b a s e d o n e x t e r n a l s t a n d a r d s

w h i c h e n c o m p a s s e d t he c o n c e n t r a ti o n s o f t he u n k n o w n s o rs a m p l e s .2 .4 . S t a t i s t i c a l m e t h o d s

W e e m p l o y e d a m u l t i v a r i at e t e s t in g p r o c e d u r e , n a m e l ya f o r w a r d , s t e p w i s e m o v i n g , l o g i s t i c m u l t i v a r i a t e r e g r e s -s i o n m o d e l . T h i s p r o c e d u r e w a s u s e d n o t o n l y t o p i c k o u tt h e s i g n i f i c a n t v a r i a b l e s t h a t e x p l a i n t h e l o g i s t i c m o d e l , b u ta l s o t o i d e n t if y t h e d i s t i n c t iv e p r o f i l e s o f t h e d i c h o t o m o u sd e p e n d e n t v a r i a b le . T h i s a n a l y s i s w a s u s e d t o s e p a r a t e l ys t u d y d i f f e r e n c e s i n g r o u p , s e x a n d d i c h o t o m i z e d a g e , f o rb i n d i n g t o t h e 5 - H T I A a n d t h e s e r o t o n i n t r a n s p o r t e r r e c e p -t o r s . P o s t - r e g r e s s i o n a n a l y s e s w e r e c a r r i e d o u t , u s i n g p a i r e dt - t e s t s f o r t h e s i g n i f i c a n t v a r i a b l e s . T h e d e s c r i p t i v e s t a t i s -t i c s o n t h e s e v a r i a b l e s a n d c o r r e l a t i o n s w e r e i n c l u d e d t os u p p o r t a n d c o m p l e m e n t t h e a n a l y s i s . S P S S W l N D O W S( 6 .0 ) w a s u s e d t o a n a l y z e t h e d a t a .

B i n d i n g t o 5 - H T j A s i t e s i n e a c h b r a i n w a s e x a m i n e d i n

Fig. 1. P seudocolor images o f subtracted autoradiograms representing total specific 5-HTIA (A, left panel) and serotonin transporter (B, right panel)binding sites in adjacent coronal sections of the prefrontal cortex of the human. N ote that: (1) the distribution of 5-HTIA receptors is lam inar and m ost ofthe binding is localized in a band ov erlaying cortical layer II in all cortical areas; (2) Binding to the serotonin transporter is higher in the outer corticallayers and densest in the medial prefrontal cortex; (3) b inding to the gray m atter is much greater than to the w hite matter for both pre-and postsynapticsites.


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V. Arango et al. / Brain Research 688 1995) 121-133 1251 0 3 b a n d s i n v o l v i n g n i n e B r o d m a n n a r e a s ( su l c u s a n dg y r u s ) a n d 1 8 p a i r s w e r e i n c l u d e d i n t h e a n a l y s i s . T h en a t u ra l l o g a r i t h m s o f t h e s e 1 0 3 m e a s u r e s w e r e t a k e n t or e d u c e s k e w n e s s , a n d c o n s t i t u t e d t h e v a r i a b le s t o b e t e s t e df o r 5 - H T I A d i f f e r e n c e s . B i n d i n g t o t h e s e r o t o n i n t r a n s -p o r t e r w a s s t u d i e d i n 4 3 b a n d s , u s i n g d a t a o n 2 2 m a t c h e dp a i r s o f s u b je c t s . T h e b i n d i n g l e v e l s in t h e s e 4 3 b r a i nr e g i o n s w e r e n o t t r a n s f o r m e d a s t h e r e w a s l i t t l e s k e w n e s s .

C o r r e l a t i o n s w i t h a g e , P M I a n d f r e e z e r s t o r a g e t i m ew e r e c a l c u l a t e d u s i n g t h e P e a r s o n s c o e f f i c i e n t o f c o rr e l a -t i o n . M i s s i n g c e l l s w e r e r e p l a c e d b y t h e i r c o r r e s p o n d i n gs u b g r o u p m e a n s f o r e a c h o f t h e re c e p t o r p o p u l a t i o n s .R e s u l ts a r e r e p o r t e d a s m e a n + s t a n d a r d e r r o r o f t h e m e a n .A l l P v a l u e s a r e t w o - t a i l e d . A l p h a w a s p r e s e t a t P < 0 .0 5 .2.5. Subjects

D e m o g r a p h i c v a r i a b l e s f r o m s u i c i d e a n d c o n t r o l s u b -j e c t s w e r e s i m i l a r. T h e m e a n a g e o f th e s u i c id e g r o u p w a s4 1 . 5 + 4 . 1 4 y ( 1 4 - 7 8 ) c o m p a r e d t o 4 1 . 3 + 4 . 4 y e a r s ( 1 5 -7 9 ) f o r t h e c o n t r o l s ( t = 0 .2 3 , 2 1 d f , P = 0 .9 8 ) . T h e P M Io f th e s u i c i d e g r o u p w a s 1 4 . 2 + 0 .3 h ( 4 - 2 2 h ) c o m p a r e dt o 1 3 . 9 + 0 . 2 h ( 4 - 2 2 ) f o r t h e c o n t r o l s ( t = 0 .8 3 , 2 1 d f ,P = 0 . 7 8 ). T h e r a t i o o f m e n t o w o m e n w a s 1 4 : 8 i n e a c hg r o u p . T h e m e a n f r e e z e r s t o r a g e t i m e ( t i m e f r o m t i s s u ec o l l e c t i o n t o a s s a y ) f o r s a m p l e s a s s a y e d f o r 5 - H T I A b i n d -i n g in t h e s u ic i d e g r o u p w a s 5 1 8 . 8 + 5 5 . 5 d a y s c o m p a r e dt o 5 2 5 . 5 + 4 7 . 5 d a y s f o r t h e c o n t r o l g r o u p ( t = 0 . 1 4 , 1 7 d f ,P = 0 . 8 2 ). L i k e w i s e , t h e s t o r a g e t i m e f o r s a m p l e s a s s a y e df o r t h e s e r o t o n i n t r a n s p o r t e r w a s n o t d i f f e re n t i n t h e t w og r o u p s ( 6 2 2 .6 + 4 0 .1 d v s . 5 8 7 .5 + 3 1 .2 d a y s ; t = 0 .8 2 , 2 1d f , P = 0 .4 2 ) . C a u s e s o f d e a t h i n th e s u i c i d e g r o u p w e r e :h a n g i n g ( 1 0 ) , f a l l f r o m h e i g h t ( 6 ) , f i r e a rm ( 4 ) , s u b w a y ( 1 )a n d i n g e s t i o n o f l y e (1 ) . I n t h e c o n t r o l s , c a u s e s o f d e a t hw e r e : f a l l ( 3 ), m o t o r v e h i c l e a c c i d e n t (8 ) , f i r e a r m ( 3 ) ,c a r d i a c f a i l u r e ( 3 ) , l a c e r a t i o n s ( 2 ) , e x p l o s i o n ( 1 ) , a n e u r i s m( 1 ) a n d r e s p i r a t o r y f a i l u r e ( 1 ). T h e s e c r i t e r i a f o r m a t c h i n gp a i r s e n a b l e d u s t o l i m i t p o s s i b l e v a r i a n c e d u e t o P M I , s e x ,s t o r a g e a n d a g e , t h a t m a y a f f e c t r e c e p t o r b i n d i n g . A s s a y -i n g t h e m a t c h e d p a i r s t o g e t h e r r e d u c e d i n t e r a s s a y v a r i a n c ee f f e c t s .2.6. Drugs and reagents

[ 3H ] 8 - O H - D P A T ( 1 2 5 - 1 6 2 C i / m m o l ) a nd [ 3H ] C N - I M I( 7 8 . 8 - 8 3 . 6 C i / m m o l ) w e r e p u r ch a s ed f r o m N e w E n g l a n dN u c l e a r ( B o s t o n , M A ) , s t o r e d i n e t h a n o l at - 8 0 C i n t h ed a r k a n d d i l u t e d i n b u f f e r i m m e d i a t e l y p r i o r t o a s s a y .S e r t r a l i n e - H C l w a s g e n e r o u s l y s u p p l i e d b y P f i z e r P h a r m a -c e u t i c a l s ( G r o t o n , C T ) . A l l o t h e r c h e m i c a l s w e r e p u r -c h a s e d f r o m S i g m a C h e m i c a l C o ( S t. L o u i s , M O ) .

3 R e s u l t s

G y r a l a n d s u l c a l c o r t e x e x h i b i t d i f f e r e n t c y t o - a n dm y e l o a r c h i t e c t o n i c c h a r a c t e r i s ti c s [ 7 9] , w i t h f u r t h e r d i f f e r-

6 0

99

4O

C o n t r o l s n = l 8 )S u i c i d e s n = 1 8 )

. p < 0 .05

O 3

e~5 0 . 0 5 ) .T h e b i l a m i n a r p a t te r n w a s m o s t s t r i k i n g i n th e a n t e r i o rc i n g u l a t e g y r u s , w h e r e t h e o u t e r b a n d h a d m o r e t h a n t w i c e

2 5

2 0EO

15~5.c_rn

.o_ 5

~ C o n t r o l ( n = 2 2 )S u i c i d e ( n = 2 2 )

p < 0 . 0 5

< 7

8 9 4 6 4 5 4 7 1 1 1 2 3 2B r o d m a n n A r e a s

Fig. 4. [3H]CN-IM I bind ing in sulci of Brodmann areas across prefrontal cortex: a comparison o f suicides and controls. Bar graph comparing the specificb inding of [ 3HICN-IM I to serotonin transporter sites between the suicide and control group s across the entire thickness of the sulcal gray m atter in multiplcBrodman n areas of the prefrontal cortex . Specific bindin g is expressed in fm ol /m g tissue + S.E.M . for 22 subjects in each group. As w ith previousfigures, data for each subject represents mean values obtained from 3 subtracted autoradiograms. Analyses between groups were done by paired t-tests.


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128 V Arango et al. / Brain Research 688 1995) 121-133t h e l e v e l o f b i n d i n g o f t h e i n n e r b a n d . T h e b i l a m i n a rp a t t e rn o f r e c e p t o r d i s t r ib u t i o n w a s p r e s e r v e d i n s u i c i d ev i c t i m s . L e v e l s o f b i n d i n g d i f f e re d g r e a t l y a c r o s s c o r t i c a la r e a s w i t h i n t h e p r e f r o n t a l c o r t e x , a n d w a s m o r e t h a n f o u rt i m e s h i g h e r i n t h e a n t e r i o r c i n g u l a t e g y r u s t h a n i n t h ea s s o c i a t i o n c o r t e x o f a r e a 9 . A s w i t h 5 - H T ~ A b i n d i n g , t h ep a t t e r n o f d i f f e r e n t i a l b i n d i n g t o t h e s e r o t o n i n t r a n s p o r t e ra c r o s s B r o d m a n n a r e a s i n p r e f r o n t a l c o r t e x w a s p r e s e r v e di n s u i c i d e v i c t i m s .

T h e m u l t i v a r i a t e s t a ti s t ic a l p r o c e d u r e u s e d f o r s e r o t o n i nb i n d i n g a n a l y s e s i s t h e s a m e a s a b o v e . T h e v a r i a b l e s w e r en o t t r a n s f o r m e d b e c a u s e s k e w n e s s i n th e r e c e p t o r b i n d i n gl e v e l s w a s n e g l i g i b l e . A s p o i n t e d o u t e a r l ie r , t h e l o g i s t ica n a l y s i s w a s p e r f o r m e d t h r e e t i m e s t o s t u d y g r o u p , s e x a n da g e d i f f e r e n c e s u s i n g b i n d i n g l e v e l s ( f m o l / m g t i s su e ) ina l l 4 3 r e g i o n s ( b a n d s ) . T h e r e s u l ts a r e p r e s e n t e d s e p a r a t e l yf o r e a c h o f t h e t h r e e v a r i a b l e s .G r o u p d i f f e r e n c e s

T h e c o n t r o l a n d s u i c i d e g r o u p s w e r e i d e n t i f ie d b y t h em o d e l u s i n g t h e b i n d i n g d a t a f r o m o n l y o n e r e g i o n , n a m e l y ,i n n e r b a n d o f g y r a l a r e a 4 6 ( 5 . 9 6 ___ 0 . 4 3 f o r t h e c o n t r o lg r o u p v s . 4 . 7 2 + 0 . 4 2 f o r t h e s u i c i d e g r o u p ) . T h e r e w e r et h i rt e e n m i s m a t c h e s o u t o f a t o ta l 4 4 o b s e r v a t i o n s , y i e l d i n ga n a c c u r a c y o f 7 1 . T a b l e 3 p re s e n t s t h e m o d e l p a r a m e -t e rs . S e r o t o n i n t r a n s p o r t e r b i n d i n g w a s l o w e r i n t h e s u i c i d eg r o u p i n 4 2 o f th e 4 3 b r a i n r e g i o n s ( W i l c o x o n M a t c h e d -P a i r s S i g n e d - R a n k s T e s t , P < 0 . 0 0 0 1 , s e e F i g . 4 ) . T h ee x c e p t i o n w a s i n th e i n n e r b a n d o f g y r a l a r e a 3 2 . T h ed e c r e a s e i n b i n d i n g w a s m o r e p r o n o u n c e d i n B r o d m a n na r e a s 4 5 a n d 4 6 , t h e d i f fe r e n c e r a n g i n g b e t w e e n 1 6 a n d2 7 . I n t h e o t h e r c o r t i c a l r e g i o n s , t h e d i f f e r e n c e r a n g e db e t w e e n z e r o a n d 2 1 .

Table 3Mod el coefficients for serotonin transporter receptor binding in p refrontalcortex: significant variables identified by the logistic regression analysisin a g roup of suicide victims and controlsVariable: GroupVariable Value of Sig. of Wald 'scoeff icient s tat .(P)465UGIN - 0.3320 0.0472Constant 1.7772 0.0730Variable: SexVariable Value of Sig. of Wa ld'scoefficient stat. (P )325U SIN - 0.4821 0.0081Constant 2.7435 0.0261a The variable nam es are constructed as follows: the first two digitsindicate the Brodm ann are a; U identifies the serotonin transporter (up-take) site, followed by S (sulcus) or G (gyrus); the n ex t two charactersindicate the in ner (IN) co rtical lam inae corresponding to an isodensityband.

P o s t - h o e p a i r e d t - te s t s s h o w e d t h a t p r o b a b i l i t ie s a s so c i -a t e d w i t h t h e m e a n v a l u e s f o r t h e s e r o t o n i n t r a n s p o r te rb i n d i n g w e r e s i g n i f i c a n t i n si x b a n d s i n a r e a s 4 5 a n d 4 6 .T h e m e a n v a l u e s f o r th e s u i c i d e g r o u p w a s l o w e r th a n t h ec o n t r o l g r o u p i n a l l t h e s i x s i g n i f i c a n t r e g i o n s . T a b l e 4p r e s e n t d e t a i l s o f t h e s e r e s u l t s .S e x d i f f e re n c e s

T h e i n n e r l a y e r s o f s u l c a l a r e a 3 2 ( 8 . 5 6 + 0 . 6 1 f o rm a l e s v s . 5 . 5 2 + 0 . 5 1 f o r f e m a l e s ) h a d s i g n i f i c a n t l y d i f f e r -e n t b i n d i n g . M a l e a n d f e m a l e s u b j e c t s w e r e i d e n t i fi e d w i tha m i s m a t c h o f t w e l v e s u b j e c ts , y i e l d i n g a c l a s s i fi c a t i o n

25

~ 20

vt~ 15._=~5-~ 10

0

~ Males n=28)Females n=16)

* p < 0.05

i i i .

l I i8 9 46 45 47 11 12 32

Brodmann AreasFig. 5. Sex differences in [3H]CN-IM I binding in sulci of Brodman n areas across prefrontal cortex. Bar g raph comparing the specific binding of[3H]CN-IMI to serotonin transporter sites between m ales (light stipple) and females (dark stipple) across multiple Brodmann areas in the prefrontal cortex.Specific binding is expressed in fmo l/m g tissue + S.E.M. for 28 m ales and 16 fema les. Da ta for eac h subject was obtained as described in Figs. 2, 3 and5. D ifferences between sexes were present in all areas m easured.


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V. Arango et al. / Brain Research 688 (1995) 121-1 33 129

Table 4Post-hoe paired t-testsBrodmann areas 45 and

for serotonin transporter receptor binding in46

Variable Mean + S.E.M. t P (2-tailed )Brodmann area 45Sulc al gray C: 11.39 -+ 1.20

S: 8.36 +0.91 2.72 0.013Inner band, Sulcus C: 8,60 + 0.82S: 6.43+_0.65 2.59 0,017Outer band, Sulcus C:1 5.1 9+ 1.69

S: 11.1 6+ 1.29 2.64 0.015Brodmann area 46Gyral gray C: 7.01 + 0.54

S: 5.56+_0.52 2.23 0.037Inner band, Gyru s C: 5.96 _+ 0.43

S: 4.71 _+ 0.42 2.20 0.039Outer band, Gyrus C: 7.95 + 0.66

S: 6.34 +0. 62 2.22 0,037~ fm ol /m g tissue, obtained from 22 pairs of suicides and controls.Degrees of freedom for all = 21. C = control group; S = suicide group.

a c c u r a c y o f 7 2 .7 . Ta b l e 3 d e s c r i b e s t h e d e t a i ls . Fe m a l e sh a d l o we r b i n d i n g t h a n m a l e s i n a l l c o r t i c a l b r a i n r e g i o n se x a m i n e d ( b u t n o t i n wh i t e m a t t e r , F i g . 5 ) a n d t h e p e r c e n t -a g e d i f f e r e n c e r a n g e d f r o m 1 5 t o 3 8 ( P < 0 .0 0 0 1 ) .Age d i f f e rences

Th e l o g i s t i c r e g r e s s i o n a n a l y s i s d i d n o t d e t e c t a n y r e -g i o n wh e r e a g e d i f f e r e n c e s we r e s i g n i f i c a n t .3.3. Correlat ions between 5-1 ITIA and serotonin trans-por te r b ind ing

Co r r e l a t i o n s we r e s t u d i e d wi t h i n Br o d m a n n a r e a s 4 5a n d 4 6 f o r t h e t w o b i n d i n g s i te s . I t s h o u l d b e n o t e d t h a t th ei s o d e n s i t y b a n d s f o r t h e t wo s i t e s a r e q u i t e d i f f e r e n t a n d s oa n e x a c t m a t c h f r o m t h e s a m e c o r t i c a l l a y e r s wa s n o t d o n e .I n s t e a d w e c o m p a r e d s u l c a l o r g y r a l s u b r e g i o n s f r o m t h es a m e B r o d m a n n a r e a s . I n B r o d m a n n a r e a 4 5 , c o r r e l a t i o nb e t we e n t h e l o g t r a n s f o r m e d b i n d i n g v a l u e f o r 5 - HTI A i ng y r a l o u t e r l a y e r I l l a n d t h e b i n d i n g f o r s e r o t o n i n t r a n s -p o r t e r in t h e in n e r g y r a l l a y e r s wa s r = - 0 . 3 4 1 ( P = 0 . 0 4 ) ,wh i l e t h a t f o r g y r a l l a y e r s I l l - I V f o r 5 -HT1 A wi t h t h e i n n e rl a m i n a e fo r se r o t o n in t r a n s p o r te r b i n d i n g w a s r = - 0 . 3 9 4( P = 0 .0 1 9 ) . T h e b i n d i n g i n t h e s u l c a l r e g i o n s f o r t h e s et wo r e c e p t o r s h a d f i v e s i g n i f i c a n t c o r r e l a t i o n s r a n g i n gf r o m r = - 0 . 3 5 3 t o r = - 0 . 4 3 6 w i t h p r o b a b il i ti e s b e -t we e n 0 . 0 3 7 a n d 0 . 0 0 9 . Th e r e g i o n s i n v o l v e d we r e t h es u l c a l l a y e r I I , I I I - I V a n d t h e g r a y m a t t e r f o r 5 -HT1 A a n dt h e i n n e r l a m i n a e o f g y r u s a n d s u l c u s f o r t h e t r a n s p o r t e r .Ar e a 4 6 h a d t h r e e s i g n i f i c a n t c o r r e l a t i o n s i n v o l v i n g t h ei n n e r a n d o u t e r s u l c a l l a y e r s f o r t h e s e r o t o n i n t r a n s p o r t e ra n d t h e s u l c a l g r a y f o r 5 -HTt A , th e r v a l u e s r a n g i n g f r o m- 0 . 3 7 2 t o - 0 . 4 4 5 w i t h p r o b a b i li t ie s f r o m 0 .0 2 8 t o 0 . 0 07 .

Ot h e r b r a i n r e g i o n s h a d we a k e r , b u t n e v e r t h e l e s s , n e g a t i v ecor re la t ions .

3.4. Correla t ions with postm ortem inter l~alTh e e f f e c t o f p o s t m o r t e m i n t e r v a l o n b i n d i n g i n g y r u s

g r a y a n d s u l c u s g r a y a r e a s wa s s t u d i e d . PM I c o r r e l a t e dp o s i t i v e l y wi t h t h e b i n d i n g t o t h e s e r o t o n i n t r a n s p o r t e r i na l l Br o d m a n n a r e a s s t u d i e d . Co r r e l a t i o n v a l u e s r a n g e df r o m 0 . 4 3 9 t o 0 . 6 2 7 wi t h a s s o c i a t e d p r o b a b i l i t i e s b e t we e n0 . 0 0 8 a n d 0 . 0 0 0 . Th e e f f e c t o f PM I wa s m o s t d r a m a t i c i nthe group wi th the shor t PMI ( l ess than or equa l to 15 .9 h ,t h e m e d i a n PM I f o r t h e s a m p l e ) . Th e r e we r e n o c o r r e l a -t i o n s b e t we e n 5 - HT1 A a n d PM I . Th e g r o u p wi t h PM Ig r e a t e r t h a n t h e m e d i a n ( > 1 5 . 9 h ) d i d n o t c o r r e l a t e wi t hb i n d i n g t o e i t h e r s i t e . Th u s t h e b i n d i n g t o t h e t r a n s p o r t e rs e e m s t o b e t e m p o r a l l y d e p e n d e n t.

An o t h e r a s p e c t o f th e e f f e c t o f PM I o n t h e s e r o t o n i nt r a n s p o r t e r i s i t s s p e c i a l a f f i n i t y f o r t h e s u i c i d e g r o u p . Th eb i n d i n g t o t h e t r a n s p o r t e r i n a l l t h e 1 4 g r a y a r e a s ( s u l c u sa n d g y r u s ) s h o we d v e r y h i g h c o r r e l a t i o n s wi t h PM I , r a n g -i n g f r o m 0 . 5 5 t o 0 . 8 1 , wi t h p r o b a b i l i t i e s f r o m 0 . 0 2 4 t o0 . 0 0 0 . N i n e o f t h e s e c o r r e l a t io n s we r e a b o v e 0 .7 . I n a d d i -t ion , the b inding was h igher in su lc i than in gyr i ( in 6 outo f 7 Br o d m a n n a r e a s ) . I n c o n t r a st , o n l y t h r e e o f t h e 1 4c o r r e l a t i o n s we r e s i g n i f i c a n t f o r t h e c o n t r o l g r o u p ( wi t hp r o b a b i l i t i e s 0 . 0 5 t o 0 . 0 2 ) . Th e c o r r e l a t i o n s we r e n e g a t i v ea n d we r e n o t s i g n i f i c a n t f o r 5 - HT~A, r a n g i n g m o s t l y f r o m- 0 . 2 5 t o - 0 . 4 5 f o r t h e s u i ci d e g ro u p a n d a l m o s t z e r o f o rc o n t r o l s .3.5. Relat io nship betwee n serotonin 5-HIAA 5-H TP andL- try and binding s i tes

Le v e l s o f s e r o t o n i n i n Br o d m a n n a r e a 9 we r e n o td i f f e r e n t i n s u i c i d e v i c t i m s ( 6 . 9 _+ 3 . 2 p m o l / m g p r o t e i n )c o m p a r e d t o c o n t r o l s ( 6 .7 _+ 2 . 0 p m o i / m g p r o t e i n ; P =0 . 9 5 ) . L e v e l s o f 5 - H I A A f r o m t h e s a m e a r e a a l s o d i d n o td i f fe r (13 .4 _+ 2 .0 vs . 11 .7 _+ 2 .1 p m o l / m g prote in , P =0 . 5 2 ) . S i m i l a r l y , le v e l s o f th e p r e c u r s o r s L - tr y a n d 5 - H TPd i d n o t d i ff e r b e t w e e n g r o u p s . N o c o r r e l a t i o n s we r e f o u n db e t we e n l e v e l s o f s e r o t o n i n , i t s p r e c u r s o r s o r m e t a b o l i t ea n d e i t h e r 5 - HTl A o r s e r o t o n i n t r a n s p o r t e r b i n d i n g i n t h es a m e B r o d m a n n a r e a .

4 D i s c u s s i o n

Us i n g q u a n t i t a t i v e r e c e p t o r a u t o r a d i o g r a p h y we f o u n d ad e c r e a s e i n t h e b i n d i n g t o t h e p r e s y n a p t i c s e r o t o n i n t r a n s -p o r t e r , a n d a c o n c o m i t a n t i n c r e a s e i n t h e l e v e l o f p o s t-s y n a p t i c 5 - HT1 A b i n d i n g i n t h e p r e f r o n t a l c o r t e x o f s u i c i d ev i c t i m s c o m p a r e d t o c o n t r o l s . Th i s i s t h e f i r s t s t u d y t oe x a m i n e b o t h p r e - a n d p o s t s y n a p t i c s e r o t o n i n r e c e p t o r s b yq u a n t i t a t i v e r e c e p t o r a u t o r a d i o g r a p h y i n a d j a c e n t s e c t i o n sf r o m t h e p r e f r o n t a l c o r t e x o f s u i c i d e v i c t i m s a n d c o n t r o l s .

L e v e l s o f s e r o t o n i n a n d 5 - H I A A a p p e a r t o b e l o w e r i nt h e b r a i n s t e m o f s u i c i d e v i c t i m s , [ 2 ] a n d 5 - HI AA l e v e l s a r el o we r i n CSF f r o m s u i c i d e a t t e m p t e r s , [ 5 1 ] s u g g e s t i n g t h a t


10/13

3 } V . A r a n g o e t a l. / B r a i n R e s e a r c h 6 8 8 1 9 9 5 ) 1 2 1 - 1 3 3

r e duc e d se ro tone rg i c func t ion i s a ssoc i a t e d w i th su i c idea nd a t t e mp te d su i c ide . Th i s r e duc t ion a ppe a r s t o be i nde -pe nde n t o f d i a gnos t i c g roup a nd re l a t e d to a h i s to ry o f ase r ious su i c idal a c t . W e the re fo re hypo the s i z e d tha t t hepos t syna p t i c 5 -H TIA re c e p to r ma y be up re gu la t e d a nd thene rve t e rmina l se ro ton in t r a nspo r t e r ma y be r e duc e d in t hesu ic ide g roup c ompa re d to c on t ro l s .

The d i f f e re nc e s i n b ind ing l e ve l s fo r t he se ro ton int r a n sp o r t e r w e r e m o r e u n i f o r m l y w i d e s p r ea d ( 4 2 / 4 3 r e -g ions) t ha n fo r the 5 -H T1A re c e p to r (85 / 10 3 re g ions).B o th b ind ing s i t e popu la t ions i n su i c ide show e d the g re a t -e s t d i f f e re nc e s f rom c on t ro l s i n t he o rb i t a l a nd l a te ra lp re f ron ta l c o r t e x , sugge s t ing the g re a t e s t a bno rma l i t y i nsu i c ide s a re i n t he se r e g ions . Fu r the rmore , t he c o r re l a t i onsbe tw e e n the 5 -H TIA a nd se ro ton in t r a nspo r t e r b ind ingle ve l s w e re found to be ne ga t ive i n more tha n 90 o f there g ions s tud ie d . Thus , w e f ind bo th a ne ga t ive c o r re l a t i onin b inding to the 5-HT1A receptor and the se roton in t rans-porte r in both groups, as wel l as s ignif icant changes inthe se p re - a nd pos t syna p t i c se ro ton in r e c e p to r s i n su i c idev ic t ims c ompa re d to c on t ro l s i n ve n t ro l a t e ra l p re f ron ta lcor tex . We in te rpre t these resul ts to suggest tha t there i s anunde r ly ing c om mo n in f lue nc e on 5 -H T~A a nd se ro ton int ransporte r b inding, and th is inf luence resul ts in changes inoppos i t e d i r e c t ions on the tw o re c e p to r sub type s .

Ea r l i e r b ind ing s tud ie s o f 5 -H T re c e p to r s in su i c idev ic t ims [23 ,54 ,58 ,59 ] u se d [3H ]5 -H T in homo ge na te s f romfron ta l c o r t e x a nd o the r r e g ions . N one o f t he se s tud ie sre po r t e d a ny d i f f e re nc e s be tw e e n g roups , pe rha ps be c a usesuc h a n a pp roa c h fa i l s t o d i s t i ngu i sh be tw e e n se ro ton inre c e p to r sub type s . [3H ]5 -H T b inds w i th na nomola r a f f in i tyto 5 -H T1A , 5 -H Tic , 5 -H T1D and p roba b ly o the r r e c e p to rsub type s . More r e c e n t s tud ie s a re i n d i sa g re e me n t a s t owh ether there i s an increase in 5-HT1A binding in su ic ides( se e [2 ,55 ] fo r r e v i e w ) . O ne s tudy found a n inc re a se i nB m a x i n t he do r sa l p re f ron ta l c o r t e x o f nonv io l e n t su i c ide s(but not in v io lent su ic ides) compared to contro ls [56] .A no th e r s tudy found inc re a se d 5 -H T 1A b ind ing in t hee n to rh ina l c o r t e x a nd h ippoc a mp us o f v io l e n t su i c ide s [38 ].The b ind ing to 5 -H TIA s i te s , a s l a be l e d by [3H ]5 -H T , w a sre po r t e d to be una l t e re d in f ron ta l a nd t e mpora l c o r t e x o fde p re sse d su i c ide v i c t ims c ompa re d to c on t ro l s [21 ] . Morerecent s tudies wi th nega t ive resul ts , using the se lec t ive5 -H T~A re c e p to r a gon i s t [3H ]8 -O H -D PA T a s t he l i ga nd ,ha ve a l so ha d me thodo log ic a l l im i t a t i ons . Fo r e xa mple ,Di l lon e t a l . [26] found no d i ffe rence in 5-HTIA bindingbe tw e e n su i c ide a nd c on t ro l g roups e i t he r i n homoge na te sf r o m p r e / p o s t c e n t r a l g y r i o r i n s e v e r a l f r o n t o - t e m p o r a ic o r t i c a l a nd subc o r t i c a l r e g ions by a u to ra d iog ra phy , bu tthe i r p ro toc o l d id no t i nc lude ma sk ing fo r se ro ton in t r a ns -po r t e r s i t e s . S inc e se ro ton in t r a nspo r t e r s i t e s ma y be r e -d u c e d i n n u m b e r , n o t b l o c k i n g [ 3 H ] 8 - O H - D P A T b i n d i n gto the t ransporte r may resul t in fa i lure to de tec t increase in5-HT1A binding.

Mos t o f t he s tud ie s o f t he se ro ton in t r a nspo r t e r i nsu i c ide v i c t ims ha ve u se d homoge na te s a nd [3H ] imip ra -

mine as the l igand. These studies have not d is t inguishedbe tw e e n [3H ] imip ra mine b ind ing to the h igh - v s . l ow -a f f in -i ty s i tes [19 ,37] , a l though only the h igh-aff in i ty s i te corre -sponds to the se rotonin t ransporte r [24] . In contrast ,[3H ]C N -IMI on ly b inds t o a s ing le , h igh -a f f in i ty s i t e[27 ,35 ,42 ] , p roba b ly the phys io log ic a l ly impor t a n t one .[3H]p aroxe t ine , a nontr icyc l ic se rotonin uptak e inhibi tor ,ha s a dva n ta ge s ove r bo th [3H ]C N -IM I a nd [3H ] imip ra minein te rms of receptor spec i f ic i ty [34] , and a l though i t i s note f fe c t ive fo r huma n a u to ra d iog ra p hy (A ra ngo a nd E rns -be rge r , unpub l i she d w o rk ) , i t ma y be p re fe ra b le t o u se t h i shigh-aff in i ty se lec t ive l igand in s tudies of b inding k ine t icsin me mbra ne p re pa ra t ions .

S tud ie s o f [3H ] imip ra mine in homoge na te s f rom f ron ta lc o r t e x ha ve r e po r t e d c on f l i c t i ng r e su l t s . Mos t o f t he ses tud ie s found a de c re a se i n t he numbe r o f b ind ing s i t e s i nthe f ronta l cor tex of the suic ide group [5 ,6 ,23,62,70,71] .Three studies found no change [7 ,8 ,58] , and one studyfound an increase in these s i tes in the suic ide group [57] .In looking a t o ther bra in regions, one study [62] found a30 de c re a se in t he hypo tha l a mus o f t he su i c ide g roup ,a nd a no the r [46 ] found a de c re a se i n t he pu ta me n o fde p re sse d su i c ide v i c t ims dy ing f rom a n ove rdose . Fou rs tud ie s ha ve u se d [3H ]pa roxe t ine as t he l i ga nd a nd tw o o fthose [45,46] reported no changes in the prefronta l cor tex(B rodm a nn a re a 10 ) o f de p re sse d su i c ide v i c t ims c om-pared to contro ls . The o ther s tudies [43 ,44] found a 35a nd a 26 re duc t ion in t he p re f ron ta l a nd t e mpora l c o r t e x ,r e spe c t ive ly , o f d rug - f re e su i c ide v i c t ims c ompa re d tocontro ls [43] , and a 43 reduc t ion in prefronta l cor tex[44] . As indica ted above , [3H]imipramine is not a spec i f icl i ga nd fo r t he t r a nspo r t e r a nd the re fo re some o f t he d i f f e r -ences in resul ts may be re la ted to changes in o ther recep-to r s , suc h a s t he non - t r a nspo r t e r im ip ra mine b ind ing s i t e(protease-resis tant , not d isplaced by serotonin) , o~j-adren-ergic or muscar in ic chol inergic s i tes [24] . Moreover , i f , asour present s tudy indica tes, the decrease in t ransporte rb ind ing i s ge ne ra l iz e d bu t g re a t e r i n spe c i f i c sub re g ions o fthe p re f ron ta l c o r t e x , t hen the r e su l t s o f ho moge n a te a ssa ysa re some w ha t de pe nde n t on the a c c u ra c y o f d i s se c t ion o fspec i f ic cor t ica l regions.

Of the s ix s tudies tha t have reported no signif icantdecreases in se rotonin t ransporte r b inding in su ic ide v ic -t ims c ompa re d to c on t ro l s , fou r ha d pos tmor t e m in t e rva l sgrea te r than 35 h [2] . We found evidence of an increase inb ind ing a ssoc i a t e d w i th l ong pos tmor t e m in t e rva l s i n t hesu ic ide, bu t no t t he c on t ro l g roup . Thus , d i f f e re nc e s be -tw e e n the se g roups m a y be obsc u re d in s tud ie s w i th l onge rpos tmo r t e m in t e rva l s , be c a use b ind ing in t he su i c ide g roupma y inc re a se a nd tha t o f c on t ro l s r e ma in the sa me a c rossthe fu ll r a nge o f PM I ' s . The o the r tw o s tud ies r e po r t ing nore duc t ions i n b ind ing ha d PMI ' s sho r t e r t ha n 27 h . O n theother hand, a l l the s tudies report ing decreases in t rans-po r t e r b ind ing in t he su i c ide g roup ha d m e a n pos tm or t e minterva ls shorte r than 22 h [2 ,18,38] . The cause of theinc re a se i n b ind ing w i th i nc re a se d PMI i s unknow n .


11/13

V . A r a n g o e t al . / B r a i n R es ea r ch 6 8 8 1 9 95 ) 1 2 1 -1 3 3 131

On e p r e v i o u s s t u d y u t i l i z e d [ 3 H] i m i p r a m i n e b y a u t o -r a d i o g r a p h y [ 3 3 ] o n c o r o n a l s e c t i o n s f r o m o n e h e m i c e r e -b r u m a n d f o u n d r e d u c e d b i n d i n g i n t h e p o s t c e n t r a l g y r u s ,t h e i n s u l a r c o r t e x a n d t h e c l a u s t r u m , a n d i n c r e a s e d b i n d i n gi n s e v e r a l a r e a s o f t h e h i p p o c a m p a l f o r m a t i o n . Ou r s t u d yo f t h e p r e f r o n t a l c o r t e x i n d i c a t e s a r e l a t i v e l y l o c a l i z e dd e c r e a s e i n t h e v e n t r o l a t e r a l r e g i o n . Th u s t h e v a r i a b i l i t y o fr e s u l t s i n s t u d i e s o f t h e s e r o t o n i n t r a n s p o r t e r , m a y b e d u ei n p a r t t o t h e c h o i c e o f i i g a n d , t h e b r a i n r e g i o n e x a m i n e d ,a s we l l a s t h e a g e a n d s e x o f t h e p o p u l a t i o n s t u d i e d ,p o s t m o r t e m i n t e r v a l a n d t h e u s e o f a n t e m o r t e m m e d i c a -t ion.B i n d i n g o f [ 3 H ] 8 - O H - D P A T h a d a s i m i la r c o r ti c a l l am i -n a t i o n i n b o t h s u i c i d e v i c t i m s a n d c o n t r o l s , a n d t h e r e f o r et h e g r e a t e r b i n d i n g wa s n o t d u e t o a c h a n g e i n t h e d i s t r i b u -t i o n o r o r g a n i z a t i o n o f 5 - HT~A b i n d i n g s i t e s . I n n o r m a lb r a i n , b i n d i n g t o g y r i a n d s u l c i h a d s i m i l a r l a m i n a r o r g a n i -z a t i o n , a l t h o u g h i n t h e s u l c u s , c o r t i c a l l a m i n a e we r e t h i n -n e r a n d c l o s e r t o g e t h e r . Ho we v e r , i n b o t h s u i c i d e s a n dc o n t r o l s , b i n d i n g v a r i e d s i m i l a r l y a c r o s s c o r t i c a l a r e a sw h i c h e m p h a s i z e s t h e n e e d f o r p r e c i s e c o m p a r i s o n o f t h es a m e b r a i n r e g i o n s b e t w e e n s t u d y g r o u p s . F o r e x a m p l e ,b i n d i n g wa s h i g h e r i n t h e o r b i t a l c o r t e x a n d m e d i a l c o r t e xt h a n i n t h e d o r s o l a t e r a l c o r t e x . Su c h r e g i o n a l c o m p a r i s o n si n 5 - HT~A b i n d i n g wi t h i n m u l t i p l e r e g i o n s a t o n e c o r o n a ll e v e l a r e n o t a d d r e s s e d i n p r e v i o u s l y p u b l i s h e d n o r m a t i v estudies [63].

Th e s u g g e s t i o n t h a t g r e a t e r 5 - HT~A b i n d i n g r e p r e s e n t su p r e g u l a t i o n o f p o s t s y n a p t i c 5 -HT~A s e r o t o n e r g i c s i t e s s e c -o n d a r y t o d e c r e a s e d s e r o t o n e r g i c i n n e r v a t i o n i s , f o r t h em o s t p a r t , n o t s u p p o r t e d b y a n i m a l m o d e l s w h e r e n oa l t e r a t i o n s h a v e b e e n r e p o r t e d a f t e r c h e m i c a l l e s i o n s o f t h es e r o t o n e r g i c s y s t e m [ 3 9 , 7 3 ] . On t h e o t h e r h a n d , we h a v ef o u n d i n c r e a s e d 5 - HT~A b i n d i n g i n f r o n t a l c o r t e x o f r a t sa f t e r e l e c t r o l y t i c l e s i o n s o f t h e d o r s a l r a p h e n u c l e u s [ 7 7 ]a n d a 2 0 - 4 0 i n c r e a s e i n 5 -HT~A m RN A wa s r e p o r t e d i nr a t 1 1 d a y s a f t e r 5 , 7 - d i h y d r o x y t r y p t a m i n e l e s i o n s [ 1 6 ] , a swe l l a s a n i n c r e a s e i n 5 - HT~A i m m u n o r e a c t i v i t y i n t h eh i p p o c a m p u s 1 4 d a y s p o s t - l e s i o n [ 6 1 ] . Ou r r e s u l t s a r ec o n s i s t e n t wi t h a n u p r e g u l a t i o n h y p o t h e s i s f o r g r e a t e r 5 -HT~A b i n d i n g i n t h e v e n t r o l a t e r a l p r e f r o n t a l c o r t e x o fs u i c i d e v i c t i m s . S t u d i e s o f t h e e f f e c t o f s e r o t o n i n d e p l e t i o no n s e r o t o n i n t r a n s p o r t e r b i n d i n g a r e l a c k i n g .

Th e f u n c t i o n s o f t h e p r e f r o n t a l c o r t e x ( PFC) i n h u m a n sa r e u n k n o wn , b u t e v i d e n c e s u g g e s t s t h a t i t m a y b e i n -v o l v e d i n b e h a v i o r a l i n h i b i t i o n a n d t h e e x p r e s s i o n o f e m o -t i o n ( s e e [ 3 1 , 4 7 ] f o r r e v i e w) . Le s i o n s o f t h e PFC, e i t h e r a sa r e s u l t o f t r a u m a o r s t r o k e [ 2 5 , 6 6 , 6 7 , 7 2 ] , a r e c o m m o n l ya s s o c i a t e d wi t h t h e d e v e l o p m e n t o f d e p r e s s i o n o r a g g r e s -s i o n . Di s i n h i b i t i o n i s a l s o a c o n s e q u e n c e o f a p r e f r o n t a ll e s i o n , s u g g e s t i n g t h a t t h i s a r e a h a s a n e x e c u t i v e i n h i b i t o r ya c t i o n . Ep i l e p s y i n v o l v i n g t h e f r o n t a l c o r t e x , p a r t i c u l a r l yt h e r i g h t h e m i s p h e r e , h a s b e e n a s s o c i a t e d wi t h p a t h o l o g i c a lc r y i n g [ 6 7 ] . An e a r l y s t u d y [ 7 8 ] o f p a t i e n t s wi t h l o c a l i z e df r o n t o t e m p o r a l l o b e c o n t u s i o n v s . b r a i n s t e m c o n t u s i o ns h o we d t h a t 5 - HI AA i n t h e c e r e b r o s p i n a l f l u i d wa s r e -

d u c e d i n t h e f i r s t g r o u p , c o m p a r e d t o c o n t r o l s a n d t o t h o s ep a t i e n t s wi t h b r a i n s t e m d y s f u n c t i o n , a c o n d i t i o n wh i c hp e r s i s t e d f o r 6 m o n t h s . Dy s f u n c t i o n o f t h e p r e f r o n t a l c o r -t e x m a y b e t h e r e s u l t o f d a m a g e d s u b c o r t i c a l a f f e r e n tp a t h wa y s i n c l u d i n g s e r o t o n e r g i c f i b e r s . Le s i o n s o f s u b c o r -t i c a l p a t h wa y s m a y a t l e a s t p a r t l y r e s u l t i n r e d u c e d s e r o -t o n e r g i c i n p u t . A l t e r n a t i v e l y , a n a b n o r m a l i t y m a y e x i s t a tt h e l e v e l o f s e r o t o n i n c e l l b o d i e s i n th e r a p h e n u c l e i, wh i c ha r e y e t t o b e s t u d i e d d i r e c t l y . Re g a r d l e s s o f t h e s i t e o f t h eles ion , the resul t of loss of se ro tonin input in to the pre-f r o n t a l c o r t e x m a y r e s u l t in b o t h d i s i n h i b i t io n a n d a f f e c t i v ec h a n g e s t h a t l e a d t o s u i c i d a l a c t s .

Fu t u r e p o s t m o r t e m s t u d i e s s h o u l d a d d r e s s t h e l o c a t i o no f a l t e r e d s e r o t o n i n i n p u t i n t e r m s o f c e l l b o d i e s , f i b e rp a t h wa y s , n e r v e t e r m i n a l s o r t a r g e t c o r t i c a l n e u r o n s . Th e s es t u d i e s s h o u l d a l s o c o n f i r m t h a t t h e a s s o c i a t i o n o f a l t e r e ds e r o t o n i n f u n c t i o n a n d s u i c i d e i s i n d e p e n d e n t o f d i a g n o s i sb y c o n d u c t i n g c a r e f u l p s y c h o l o g i c a l a u t o p s i e s .

c know l e dg emen t sW e g r a t e f u l l y a c k n o wl e d g e t h e a s s i s t a n c e o f t h e f o l l o w-

i n g p e o p l e ( l i s t e d a l p h a b e t i c a l l y ) : M i c h e l l e L . Al l e n ( a u t o -r a d i o g r a p h y ) , Vi c t o r V . Ar k h i p o v ( t i s s u e c o l l e c t i o n ) ,M i h r a n J . Ba k a l i a n ( d a t a m a n a g e m e n t ) , Da v i d A. Br e n t ,M . D. , De n i s e M . Gi l l e n ( a u t o r a d i o g r a p h y ) , Th e o d o r e F .L a g a t t u ta ( H P L C a s s a y s) , P a t r ic k J . M c D e v i t t ( i m a g e a n a l -y s i s ) , Ta m m y A. M i e c z k o ws k i ( s t a t i s t i c a l a n a l y s e s ) ,W i l l i a m E . M i l le r ( d e t e r m i n a t i o n o f b i n d i n g k i n e t i c s a n da u t o r a d i o g r a p h y a s s a y s ) , Br i a n W . R i g a t t i ( t i s s u e c o l l e c -t i o n ) a n d Ro b e r t W . Sm i t h ( i m a g e a n a l y s i s ) . Su p p o r t e d b yP H S G r a n t s M H 4 0 2 1 0 , A A 0 9 0 0 4 , M H 4 7 0 9 7 a ndM H 4 6 7 4 5 .

References[1] Arang o, V., Ernsberger, P., M arzuk, P.M., Chen, J.-S., Tierncy, H.,Stanley, M., Reis, D.J. and Mann, J.J. Autoradiographic demonstra-tion of increased serotonin 5-HT2 and /3-adrenergic e cepto r bindingsites in the brain of su icide victims, Arch. Gen. Psychia t ry , 47(1990) 1038-1047.[2] Arango, V. and M ann, J . J . Relevan ce of serotonergic postmortemstudies to suicidal behavior, In t . Rec. Psychia t ry , 4 (1992) 131-140.[3] Aran go, V., Miller, W .E., Miller, M.L., Underwood, M.D ., Smith,R.W. and Mann, J.J., Quantitative autoradiography of 5-HTIA bind-ing in suicide, Soc. Neurosci . Abs t r . 17 (1991) 1472.[4] A rango, V., Underwood, M.D ., McD evitt, P.J., Gu bbi, A.V. and

M a n n J . J . Localized alterations in pre-and p ostsynaptic serotoninbinding sites in prefrontal cortex of suicide victims, Soc. Neurosci .A b s t r . 20 (199 4) 26.[5] Arat6 , M., Tekes, K., P alkovits, M., D eme ter, E. and Falus, A.Serotonergic split brain and suicide, P s ych i a t r y R es . 21 (1987)355-356.[6] Arat6, M., T ekes, K., T 6thfalusi, L., M agya r, K., Palkov its, M.,Frecska, E., Falus, A. and M acCrimmon,D.J., R eversed hemisphericasymmetryof imipraminebinding in suicide victims, Biol . Psychia-t~ , , 29 (1991) 699-702.


12/13

132 V. Ar ango e t a t . /B r a in Res ear ch 688 1995) 121 -13 33 . . . . .[7] Arora, R.C. and Meltzer, H.Y. , H-lm lpramln e binding m the frontal

cortex of suicides, Psychiatry Res . 30 (1989) 125 -135 .3 .[8] Arora, R.C. and Meltzer, H.Y. , Lateral i ty and H-lm lpramm e bind-

ing: S tudies in the f rontal cor tex of normal controls and suicidevict ims , Biol . Psychiatry, 29 (1991) 1016-1022 .

[9] Agren, H. , Symptom patterns in unipolar and bipolar depress ioncorrelat ing with monoamine metaboli tes in the cerebrospinal f lu id .II. Suicide, Psychia try Res . , 3 (1980) 225 -236 .

[10] Asberg, M. , Tr~iskman, L. and Thor~n, P . , 5-H IAA in the cere-brospinal fluid. A biochemical suicide predictor? Arch. Gen. Psychi-atry, 33 (1976) 1193-1197 .

[11] Ban ki, C.M., Arat6, M., Papp, Z. and Kurcz, M ., Biochem icalmarke rs in suicidal pat ients. Inves t igat ions with cerebrospinal f lu idamine metaboli tes and neuroendocr ine tes ts , J. Affect. Disord., 6(1984) 341 -350 .

[12] Beskow , J., Gottfries, C.G., Roos, B.E. and Winbl ad, B., Determ ina-t ion o f m onoam ine and m onoam ine m etabo l i t e s in the hum an b ra in :pos t mortem s tudies in a group of suicides and in a control group,Acta Psychiat. Scand., 53 (1976) 7 -20 .

[13] Bourne, H.R., Bunney, W.E.J., Colburn, R.W., Davis, J.M., Shaw,D.M. and Coppen, AJ . , Noradrenaline, 5 -hydroxytryptam ine, and5-hydroxy indoleace t ic acid in hindbrain s of suicidal patients , L ance t ,i i ( 1968) 805 -808 .

[14] Bradley, P.B., Engel, G., Feniuk, W ., Fozard, J.R., Humphrey,P.P.A., Middlemiss, D.N., Myle chara ne, E.J., Rich ardso n, B.P. andSaxena, P .R. , Proposals for the class if icat ion and nom enclature offunctional receptors for 5-hydroxytryptamine, Neuropharmacology,25 (1986) 563-:576.

[15] Branchek, T. , Receptor divers i ty: more serotonin receptors , Curr.Biol . , 3 (1993) 315 -317 .

[16] Brousseau, D. , Wieland, S . , Lucki , I . and M cGonigle, P . , 5-HTdeplet ion al ters the levels of 5-HTla receptor mRN A, Soc. N eurosci.,17 (1991) 719.

[17] Brown, G.L. , Goodwin, F .K. and Bunney, W.E.J . , Human aggres-s ion and suicide: their relat ionship to neuropsychiatr ic diagnoses andserotonin metabolism, AdL,. Biochem. Psychopharmacol., 34 (1982)2 8 7 - 3 0 7 .

[18] Carpenter, W.T., Jr. , Bu chan an, R.W., Kirkpatrick, B., Tam mi nga,C. and Wood, F . , S trong inference, theory tes t ing, and the neu-roana tom y o f s ch izophren ia , Arch. Gen. Psychiatry, 50 (1993)8 2 5 - 8 3 1 .

[19] Cash, R., Raisman, R., Ploska, A. and Agid, Y., High and lowaff ini ty [3H]imipramine binding s i tes in control and Parkinson ianbrains , Eur. J. Pharmacol., 117 (1985) 71 -80 .

[20] Center for Disease Control and Prevention, Advance repor t of f inalmortality statistics, 1990, Mthly Vital S tat. R epor t , 41 (1993) 1-52.

[21] Cheetham, S .C. , Crompton, M.R. , Katona, C.L.E. and Horton, R.W.Brain 5-HT 1 binding s i tes in depressed suicides , Psychopharmacol-ogy Berlin), 102 (1990) 544 -548 .

[22] Coccaro, E.F., Siever, L.J., Klar, H.M., Maurer, G., Cochrane, K.,Cooper, T.B., Mohs, R .C. and Dav is, K.L., Seroto nergic studies inpatients with affect ive and personali ty disorders , Arch. Gen. Psychi-atry, 46 (1989) 587 -599 .

[23] Crow, T.J., Cross, A.J., Cooper, S.J., Deakin, J.F.W., Ferrier, I.N.,John son, J.A., Joseph, M .H., Owen, F., Poulter, M., Lofthouse, R .,Corsellis, J .A.N., C ham bers, D.R., Blessed, G., Perry, E.K., Perry,R.H. and Tomlinson, B.E. , Neurotransmit ter receptors andm onoam ine m etabo l i t e s in the b r a in s o f pa t i en t s w i th A lzhe im er - typedem entia and depression, a nd suicides. Neuropharmacology, 23(1984) 1561-1569 .

[24] D Am ato, R.J ., Largent , B.L. , S nowm an, A.M. and Snyder , S .H. ,Select ive labeling of serotonin uptake s i tes in rat brain by [3H]cita-lopram co ntras ted to labeling of m ult iple s i tes by [3 H]imipramine, J .PharmacoL Exp. Ther., 242 (1987) 364 -371 .

[25] Dam asio, H., Grabowski, T ., Frank, R., Gala burd a, A.M . and Dam a-s io , A.R. , T he return of Phineas Gage: clues abou t the brain f rom theskull of a famous patient, Science, 264 (1994) 1102-1105 .

[26] Dillon, K.A., Gross-lsseroff, R., Israeli, M. and Biegon, A., Auto-radiographic analys is of serotonin 5-HTIA receptor bind ing in thehum an brain pos tmortem: Effects o f age and alcohol, Brain Res.,554 (1991) 56 -64 .

[27] Dumbrille-Ross, A. and Tang, S.W., Bin ding of [3H]Ro 11-2465.Possible identification of a subc lass of [3 H]imipramine bind ing sites,Mol. Pharmacol., 23 (1983) 607 -613 .

[28] Dumuis, A., Sebben, M . and Bockaert, J ., The gastroint estina lprokinetic benzamide der ivat ives are agonis ts at the non-class ical5 -H T r ecep to r ( 5 -H T4) positively coupled to adenylate cyclase inneurons, Nauny n Schm iedebergs Arch. Pharmacol. , 340 (1989)403 -410 .

[29] Frazer, A. and Hensler, J .G., 5-HTjA receptors and 5-HTiA-media-ted responses: effect of treatme nts that modify serotonergic neu ro-transmiss ion, Ann . NY Acad . Sc i . , 600 (1990) 460 -475 .

[30] Fuster, J .M., The prefrontal cortex and temporal integration. In A.Peters and E.G. Jones (Eds.), Cere bral Cortex: Association an dAudito ry Cortices , Plenum Press , New York, 1985, pp. 151-177.

[31] Fuster, J.M., T he Pr e f r on ta l Cor tex - - Ana tom y , Phys io logy andNeur ops ycho logy o f the Fr on ta l L obe , Raven Press, New York, NY,1989, pp. 1-255.

[32] G ozlan, H., E1 Mestikawy, S., Pichat, L., Glowinsky, J. and Hamon,M., Identification o f presy napti c serot onin autoreceptors using a newligand: 3H-PAT, Nature, 305 (1983) 140-142.[33] Gross-lsseroff, R., Israeli, M. and Biegon, A., Autora diog raph icanalys is of t r i t iated imipramine binding in the human brain pos tmortem: effects of suicide, Arch. Gen. Psychiatry, 46 (1989) 237 -241.

[34] Habert, E., Graham, D., Tahraoui, L., Claustre, Y. and Langer, S.Z.,Characterization of 3H-paroxetine binding to rat cor tical m embran es ,Eur. J. Pharmacol., 118 (1985) 107-114.

[35] Hensler, J .G., Ferry, R.C., Labow, D .M., Kovachich, G.B. andFrazer, A., Qua ntitativ e autoradiography of the serotonin transpo rterto assess the dis tr ibution of serotonergic project ions f rom the dorsalraphe nucleus, Synapse, 17 (1994) 1-15.

[36] Henteleff , R.A. , Arango, V . and M ann, J .J . , Bin ding to serotoninuptake sites in prefrontal and temporal cortex of suicide victims,Soc. Neurosci. Abstr., 17 (1991) 1472.

[37] Hrdina, P .D., Differentiat ion of two co mpo nents of specific [ a] im-ipramine binding in rat brain , Eur. J. Pharmacol., 102 (1984)4 8 1 - 4 8 8 .

[38] Joyce, J.N., Shane, A., Lexow, N ., Winokur, A ., Casanova, M .F.and Kleinman, J .E. , Serotonin uptake s i tes and serotonin receptorsare altered in the limbic system of schizophrenics, Neuropsy-chopharmacology, 8 (1993) 315 -336 .

[39] Juorio, A.V., Li, X.M. and Boulton, A.A., T he effects of chro nict r im ip ram ine t r ea tm en t on b iogen ic am ine m etabo l i s m and ondopam ine D 2 , 5 -H T2 and tryptam ine binding s i tes in rat brain , Gen.Pharmacol., 21 (1990) 759 -762 .

[40] Kilpatrick, G.J., Jones, B.J. and Tyers, M.B., The distribution ofspecif ic bin ding of the 5-HT3 receptor l igand [3H]GR65630 in ratbrain us ing quanti tat ive autoradiography, Neurosci. Lett., 94 (1988)156-160 .

[41] Korpi, E.R., Kleinman, J., Goodman, S.I. , Phillips, l. , DeLisi, L.E.,Linnoila, M. and Wyatt, R.J., Serotonin and 5-hydroxyindoleaceticacid in brains of suicide vict ims . Comparison in chronicschizophrenic pat ients with suicide as cause of death , Arch. Gen.Psychiatry, 4 3 ( 1 9 8 6 ) 5 9 4 - 6 0 0 .

[42] Kovachich, G.B., Aro nson , C.E., Brunswick, D.J. and Frazer, A.,Quanti tat ive autoradiography of serotonin uptake s i tes in rat brainusing [3H]cyanoimipramine, Brain Res . , 454 (1988) 78 -88 .

[43] Lagattuta, T.F., Henteleff, R.A., Arango, V. and Mann, J.J. , Reduc-t ion in cor tical seroto nin transpor ter si te num ber in suicide vict imsin the absence of altered levels of serotonin, its precursors ormetabolite, Soc. Neurosci. Abstr., 18 (1992) 1598.

[44] Laruelle, M., Abi-D argh am , A., Casanova, M .F., Toti, R., Wein-berger, D.R. and Kleinman, J.E., Selective ab norm alities of pre-


13/13

V. Arango et al. / Brain Research 688 1995) 121-133 133

f r o n t a l s e r o t o n e r g i c r e c e p t o r s i n s c h i z o p h r e n i a : a p o s t m o r t e m s t u d y ,Arch. Gen. Psychiatry, 5 0 ( 1 9 9 3 ) 8 1 0 - 8 1 8 .

[ 4 5 ] L a w r e n c e , K . M . , D e P a e r m e n t i e r , F . , C h e e t h a m , S . C ., C r o m p t o n ,M . R . , K a t o n a , C .L . E . a n d H o r t o n , R . W . , S y m m e t r i c a l h e m i s p h e r i cd i s t r i b u t i o n o f ~ H - p a r o x e t i n e b i n d i n g s i t e s i n p o s t m o r t e m h u m a nb r a i n f r o m c o n t r o l s a n d s u i c i d e s , Biol. P~sychiatry, 2 8 ( 1 9 9 0 ) 5 4 4 -5 4 6 .

[ 4 6 ] L a w r e n c e , K . M . , D c P a e r m e n t i e r , F . , C h e e t h a m , S . C . , C r o m p t o n ,M . R . , K a t o n a , C . L . E . a n d H o r t o n , R . W . , B r a i n 5 - H T u p t a k e s i te s ,l a b e l l e d w i t h [ 3 H ] p a r o x e t i n e , i n a n t i d e p r e s s a n t - f r e e d e p r e s s e d s u i -c i d e s , Brain Res., 5 2 6 ( 1 9 9 0 ) 1 7 - 2 2 .

[ 4 7 ] L e v i n , H . S ., E i s e n b e r g , H . M . a n d B e n t o n , A . L . , ( E d s . ) , FrontalLobe Function and Dysfunction, O x f o r d U n i v e r s i t y P r e s s , N e wY o r k , N Y , 1 9 9 1 , p p . 1 - 4 2 7 .

[ 4 8 ] L l o y d , K . G . , F a r l e y , l . J. , D e c k , J . H . N . a n d H o r n y k i e w i c z , O . ,S e r o t o n i n a n d 5 - h y d r o x y i n d o l e a c e t i c a c i d i n d i s c r e t e a r e a s o f t h eb r a i n s t e m o f s u i c i d e v i c t i m s a n d c o n t r o l p a t i e n t s , AdL~. Biochem.Psychopharmacol., 1 1 (1 9 7 4 ) 3 8 7 - 3 9 7 .

[ 4 9 ] L o w r y , O . H . , R o s e n b r o u g h , N . J . , F a r r , A . L . a n d R a n d a l l , R . J . ,P r o t e i n m e a s u r e m e n t w i t h t h e f o l i n p h e n o l r e a g e n t , J. Biol. Chem.,1 9 3 (1 9 5 1 ) 2 6 5 - 2 7 5 .

[ 5 0 ] M a n n , J . J. , A r a n g o , V . , M a r z u k , P . M . , T h e c c a n a t , S . a n d R e i s , D . J .,E v i d e n c e f o r t h e 5 - H T h y p o t h e s i s o f s u i c id e : a r e v i e w o f p o s t - m o r t e ms t u d i e s , Br. J. Psychiatry, 1 5 5 ( S u p p l . 8 ) ( 1 9 8 9 1 7 - 1 4 .[ 5 1 ] M a n n , J . J . , M c B r i d e , P . A . , B r o w n , R . P . , L i n n o i l a , M . , L e o n , A . C . ,D e M e o , M . D . , M i e c z k o w s k i , T . A . , M y e r s , J . E . a n d S t a n l e y , M . ,R e l a t i o n s h i p b e t w e e n c e n t r a l a n d p e r i p h e r a l s e r o t o n i n i n d e x e s i nd e p r e s s e d a n d s u i c i d a l p s y c h i a t r ic i n p a t i e n t s , Arch. Gen. Psychiatry,4 9 ( 1 9 9 2 ) 4 4 2 - 4 4 6 .

[ 5 2 ] M a n n , J .J ., M c B r i d e , P . A ., M a l o n e , K . M . , D e M e o , M . D . a n d K e i l p ,J . , B l u n t e d s e r o t o n e r g i c r e s p o n s i v i t y i n d e p r e s s e d p a t i e n t s , Neu-ropsychopharmacology, i n pres s .

[ 5 3 ] M a n n , J . J . a n d S t a n l e y , M . ( E d s . ) , Psychobiology of Suicidal Behau-ior, T h e N e w Y o r k A c a d e m y o f S c i en c e s , N e w Y o r k , N Y , 1 9 8 6 , p p .1 - 3 5 7 .

[ 5 4 ] M a n n , J .J . , S t a n l e y , M . , M c B r i d e , P . A . a n d M c E w e n , B . S . , I n -c r e a s e d s e r o t o n i n ~ a n d / 3 - a d r e n e r g i c r e c e p t o r b i n d i n g i n t h e f r o n t a lc o r t i c e s o f s u i c i d e v i c t i m s , Arch. Gen. Psychiatry, 4 3 ( 1 9 8 6 ) 9 5 4 -9 5 9 .[ 5 5 ] M a n n , J .J . , U n d e r w o o d , M . D . a n d A r a n g o , V . , P o s t m o r t e m s t u d i e so f s u i c i d e v i c t i m s . I n S . J . W a t s o n ( E d . ) Biology of Schizophreniaand Affectit,e Disorders, R a v e n P r e s s , N e w Y o r k , i n p r e s s .

[ 5 6 ] M a t s u b a r a , S . , A r o r a , R . C . a n d M e l t z e r , H . Y . , S e r o t o n e r g i c m e a -s u r e s i n s u i c i d e b r a i n : 5 - H T I A b i n d i n g s i t e s i n f r o n t a l c o r t e x o fs u i c i d e v i c t i m s , J. Neural Transm., 8 5 ( 1 9 9 1 ) 1 8 1 - 1 9 4 .

[ 5 7 ] M e y e r s o n , L . R . , W e n n o g l e , L . P . , A b e l , M . S . , C o u p e t , J . , L i p p a ,A . S . , R a u h , C . E . a n d B e e r , B . , H u m a n b r a i n r e c e p t o r a l t e r a t i o n s i ns u i c i d e v i c t i m s , Pharmacol. Biochem. Beha~,., 1 7 ( 1 9 8 2 ) 1 5 9 - 1 6 3 .

[ 5 8 ] O w e n , F . , C h a m b e r s . D . R . , C o o p e r , S . J . , C r o w , T . J ., J o h n s o n , J .A . ,L o f t h o u s e , R . a n d P o u l t e r , M . , S e r o t o n e r g i c m e c h a n i s m s i n b r a i n s o fs u i c i d e v i c t i m s , Brain Res., 3 6 2 ( 1 9 8 6 ) 1 8 5 - 1 8 8 .

[ 5 0 ] O w e n , F . , C r o s s , A . J . , C r o w , T . J . , D e a k i n , J . F . W . , F e r r i e r , 1 . N .,L o f t h o u s e , R . a n d P o u l t e r, M . , B r a i n 5 - H T 2 r e c e p t o r s a n d s u i c id e ,Lancet, i i (19 83 ) 1256.[ 6 1 )] P a r e , C . M . B . , Y e u n g , D . P . H . , P r i c e , K . a n d S t a c e y , R . S . , 5 -H y d r o x y t r y p t a m i n e , n o r a d r e n a l i n e , a n d d o p a m i n e i n b r a i n s t e m ,h y p o t h a l a m u s , a n d c a u d a t e n u c l e u s o f c o n t r o l s a n d o f p a t i e n t sc o m m i t t i n g s u i c i d e b y c o a l - g a s p o i s o n i n g . Lancet, i i ( 1 9 6 9 1 1 3 3 -135.

[ 6 1 ] P a t e l , T . D . , A z m i t i a , E . C . a n d Z h o u , F . C . , I n c r e a s e d 5 - H T I A r e c e p -

t o r i m m u n o r e a c t i v i t y i n t h e r a t h i p p o c a m p u s f o l l o w i n g 5 , 7 - D H Tl e s i o n s i n t h e c i n g u l u m b u n d l e a n d f i m b r i a - f o r n i x , Behal. BrainRes., i n p r e s s .

[ 6 2 ] P a u l , S . M . , R e h a v i , M . , S k o l n i c k , P . a n d G o o d w i n , F . K . , H i g ha f f in i t y b i n d i n g o f a n t i d e p r e s s a n t s t o a b i o g c n i c a m i n e t r a n s p o r t s i tei n h u m a n b r a i n a n d p l a t e l e t ; st u d i e s i n d e p r e s s io n . I n R . M . P o s t a n dC . J . B e l l i n g e r ( E d s . ) Neurobiology of Mood Disorders., W i l l i a m sa n d W i l k i n s , B a l t i m o r e , 1 9 8 4 , p p . 8 4 6 - 8 5 3 .

[ 6 3 ] P a z o s , A . , P r o b s t , A . a n d P a l a c i o s , J . M . , S e r o t o n i n r e c e p t o r s i n t h ch u m a n b r a i n - - I l l . A u t o r a d i o g ra p h i c m a p p i n g o f s e r o t o n i n -I r e ce p -tors , Neuroscience, 2 1 ( 1 9 8 7 ) 9 7 - 1 2 2 .

[ 6 4 ] P e d i g o , N . W . , Y a m a m u r a , H . I . a n d N e l s o n , D . L ., D i s c r i m i n a t i o n o fm u l t i p l e [ 3 H ] 5 - h y d r o x y t r y p t a m i n e b i n d i n g s i t e s b y t h c n e u r o l e p t i cs p i p e r o n e i n r a t b r a i n , J. Neurochem., 3 6 ( 1 9 8 1 ) 2 2 ( / - 2 2 6 .

[ 6 5 ] P e r o u t k a , S . J. a n d S n y d e r , S . H . M u l t i p l e s e r o t o n i n r e c e p t o r s : d i f f e r -e n t i a l b i n d i n g t o H - 5 - h y d r o x y t r y p t a m m c , 3 H - l y s e r g i c a ci d d ie t h -y l a m i d e a n d H - s p l r o p e n d o l , Mol. Pharmacol., 1 6 ( 1 9 7 9 1 6 8 7 - 6 9 9 .

[ 6 6 ] R o b i n s o n , R . G . , K u b o s , K . L . , S t a r r , L . B . , R a o , K . a n d P r i c e , T . R . ,M o o d d i s o r d e r s i n s t r o k e p a t i e n t s . I m p o r t a n c e o f l o c a t i o n o f l e s i o n ,Brain, 1 0 7 ( 1 9 8 4 ) 8 1 - 9 3 .

[ 6 7 ] S a c k e i m , H . A . , G r e e n b e r g , M . S . , W e i m a n , A . L . , G u r , R .C . , H u n g e r -b u h l e r , J. P . a n d G e s c h w i n d , N . , H e m i s p h e r i c a s y m m e t r y i n t h ee x p r e s s i o n o f p o s i t i v e a n d n e g a t i v e e m o t i o n s , Arch. Neurol., 3 9( 1 9 82 1 2 1 0 - 2 1 8 .[ 6 8 ] S h a w , D . M . , C a m p s , F . E . a n d E c c l e s t o n , E . G . , 5 - H y d r o x y t r y p -t a m i n e i n t h e h i n d - b r a i n o f d e p r e s s i v e s u i c i d e s . Br. J. Psychiatry,1 1 3 ( 1 9 6 7 1 1 4 0 7 - 1 4 1 1 .

[ 6 9 ] S m i t h , R . W . , A r a n g o , V . , M i l le r , M . L ., U n d e r w o o d , M . D . a n dM a n n , J . J . , 3 H - c y a n o i m i p r a m i n e b i n d i n g i s r e d u c e d i n s u i c i d e v i c -t i m s , Soc. Neurosci. Abstr. 1 8 ( 1 9 9 2 1 1 5 9 9 .

[ 7 0 ] S t a n l e y , M . , M a n n , J . J . a n d G e r s h o n , S . , A l t e r a t i o n s i n p r e - a n dp o s t s y n a p t i c s e r o t o n e r g i c n e u r o n s i n s u i c i d c v i c t i m s , Psvchophar-macol. Bull., 1 9 (1 9 8 3 ) 6 8 4 - 6 8 7 .

[ 7 1 ] S t a n l e y , M . , V i r g i l i o , J . a n d G e r s h o n , S . , T r i t i a t e d i m i p r a m i n cb i n d i n g s i t e s a r e d e c r e a s e d i n t h e f r o n t a l c o r t e x o f s u i c i d e s , Science,2 1 6 ( 1 9 82 1 1 3 3 7 - 1 3 3 9 .

[ 7 2 ] S t a r k s t e i n , S . E . , R o b i n s o n , R . G . , B e r t h i e r , M . L . a n d P r i c e , T . R . ,D e p r e s s i v e d i s o r d e r s f o l l o w i n g p o s t e r i o r c i r c u l a t i o n a s c o m p a r e dw i t h m i d d l e c e r e b r a l a r t e r y i n f a r c t s , Brain, 1 1 1 ( 1 9 8 8 1 3 7 5 - 3 8 7 .[ 7 3 ] S t o c k m e i e r , C . A . a n d K e l l a r , K .J . , I n v i v o r e g u l a t i o n o f s e r o t o n i n - 2r e c e p t o r i n r a t b r a i n . Life Sci., 3 8 ( 1 9 8 6 1 1 1 7 - 1 2 7 .

[ 7 4 ] T a y l o r , D . P . , S e r o t o n i n a g e n t s i n a n x i e t y , Ann. NYAcad. Sci., 6 0 0( 1 9 9 0 ) 5 4 5 - - 5 5 7 .

[ 7 5 ] T e c o t t , L . H . a n d J u l i u s , D . , A n e w w a v c o f s e r o t o n i n r e c e p t o r s ,Curt. Opin. Neurobiol., 3 ( 1 9 93 1 3 1 0 - 3 1 5 .

[ 7 6 ] T r ~ is k m a n , L . , ~ , s b e r g , M . , B e r t i l s s o n , L . a n d S j 6 s t r a n d , L.,M o n o a m i n e m e t a b o l i t e s i n C S F a n d s u i c i d a l b c h a v i o r , Arch. Gen.Psychiatry, 3 8 ( 1 9 8 1 ) 6 3 1 - 6 3 6 .

[ 7 7 ] U n d e r w o o d , M . D . , B a k a l i a n , M . J . , M i l l e r , M . L . , K a t z , C . K . , L a g a t -t u t a , T . F . , M a n n , J . J . a n d A r a n g o , V . , E f f e c t o f l e s i o n s o f t h e d o r s a lr a p h e n u c l e u s o n s e r o t o n i n t r a n s p o r t e r , 5 - H T l A a n d 5 - H T ~ b i n d i n gs i t e s in ra t , Soc. Neurosci. Abstr., 1 8 ( 1 9 9 2 ) 9 2 8 .

[ 7 8 ] v a n W o e r k o m , T . C . A . M . , T e e l k e n , A . W . a n d M i n d e r h o u d , J . M . ,D i f f e r e n c e i n n e u r o t r a n s m i t t e r m e t a b o l i s m i n f r o n t o t e m p o r a l - l o b ec o n t u s i o n a n d d i f f u s e c e r e b r a l c o n t u s i o n , Lancet, i ( 1 9 7 7 1 8 1 2 - 8 1 3 .

[ 7 9 ] W e l k e r , W . , W h y d o e s c e r e b r a l c o rt e x f i s su r e a n d f o l d ? A r e v i e w o fd e t e r m i n a n t s o f g y r i a n d s u l c i . I n E . G . J o n e s a n d A . P e t e r s ( E d s . )Cerebral Cortex: Comparatit,e Structure and Et.olution of CerebralCortex, Part H, P l e n u m P r e s s , N e w Y o r k , 1 9 0 0 , p p . 3 - 1 3 6 .

Arango 1995 Localized Alteraciones in Pre- And Postsynaptic Serotonine

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