CONCLUSION: There was a statistically significant increase in the num-ber of deliveries for a primary indication of gestational hypertensionat our institution after the publication of the HYPITAT trial. Therewas no significant change in immediate maternal or neonatal out-comes for patients with gestational hypertension.

765 Human placental expression of the hydrogensulfide synthesizing system: effects ofgestational age and preeclampsiaJennifer Hodges1, Wen Wang1, Thomas Lechuga1,Louise Laurent2, Mana Parast3, Dong-bao Chen4

1University of California Irvine, Obstetrics and Gynecology, Irvine, CA,2University of California, San Diego Medical Center, ReproductiveMedicine, San Diego, CA, 3University of California San Diego,Department of Pathology, San Diego, CA, 4Univeristy ofCalifornia Irvine, Obstetrics and Gynecology, Irvine, CAOBJECTIVE: Hydrogen sulfide (H2S) is emerging as a novel gaso-transmitter that regulates angiogenesis and vasodilatation underphysiologic and ischemic conditions. H2S is synthesized primarily bycystathionine �-lyase (CSE) and cystathionine �-synthase (CBS). Pre-eclampsia is characterized by dysfunctional endothelium and im-paired angiogenesis. The hypotheses of this study are that H2S-syn-thesizing enzymes are developmentally regulated in normal humantrophoblasts and that preeclampsia affects their expression and H2Sproduction in human placenta.STUDY DESIGN: Placentas from first (8-12 wk) and second (12-18 wk)trimester (n�6/group) pregnancies were collected from elective ter-minations. Placental samples from healthy term (n�5) and severepreeclamptic (n�7) patients were collected after delivery. Placentalvillous tissues were washed in phosphate-buffered saline and eithersnap-frozen and stored in liquid nitrogen or fixed in 4% paraformal-dehyde. CSE and CBS mRNA and protein expressions were examinedby real-time PCR and Western blot. Their cellular localization wasdetermined by immunofluorescence microscopy on paraffin-embed-ded sections. Methylene blue assay was used to quantify H2S produc-tion.RESULTS: Both CBS and CSE mRNAs were detected in human placen-tas. CBS mRNA did not change (p�0.05) according to gestational agewhile CSE mRNA was increased at term compared to first trimester.Both CSE and CBS proteins co-localized with cytokeratin-7 in thesyncytiotrophoblasts lining the placental villi and increased accordingto gestational age. Expression of both proteins was low in the CD31-positive placental endothelial cells. Compared to controls, both CSEand CBS proteins were significantly increased in preeclamptic placen-tas. H2S production in the preeclamptic placentas was 1.2-fold higherto that in the controls (p�0.07).CONCLUSION: The H2S-synthesizing system is regulated in human pla-centa according to gestational age and by preeclampsia. These resultsimplicate that H2S might play a role in placental physiology and thepathophysiology of preeclampsia (Supported by NIH grants).

766 Dysfunctional vascular adaptations in human umbilicalvein endothelial cells (HUVEC) in preeclamptic pregnanciesJennifer Krupp1, Derek Boeldt2, Fu-XianYi2, Ian Bird3, Dinesh Shah1

1University of WI School of Medicine and Public Health, Obstetrics andGynecology, Maternal Fetal Medicine, Madison, WI, 2University of WISchool of Medicine and Public Health, Obstetrics and Gynecology,Madison, WI, 3University of WI School of Medicine and PublicHealth, Obstetrics and Gynecology & Pediatrics, Madison, WIOBJECTIVE: Preeclampsia (PE) occurs in 4-8% of all pregnancies. En-dothelial cell dysfunction due to PE seen on the maternal side is alsofound in the umbilical vein. Our previous studies on umbilical veinendothelium (UV endo) of fresh cord vessels showed the sustainednitric oxide production and initial and sustained Ca2� burst re-sponses of normal pregnancy are impaired in PE. The basis of thisdysfunction is unclear. Our hypothesis is these losses in Ca2� re-sponse may either be due to failed programming of cell function oractive suppression of such programming by local factors or inflam-matory mediators. Removal of UV endo from the vessels and main-tenance in vitro could indicate if recovery of function of HUVECs ispossible, so suggesting that endothelial recovery on the maternal sideat least may be possible given suitable therapy.STUDY DESIGN: HUVEC isolated from normal (N�7) and PE (N�6)subjects maintained in culture in vitro to passage 3 were imaged usingFura-2 to detect Ca2� responses to stimulation with ATP (100um).Area under the curve (AUC), total number of bursts and mean Ca2�response for the sustained phase were quantified.RESULTS: HUVEC from PE subjects do recover function (Figure) butwith an increased frequency of Ca2� bursts (* � p �0.05) relative tocontrol. There is no significant difference in the AUC between thenormal and PE HUVEC. Despite the increased Ca2� burst frequencyin PE HUVEC, peak height is reduced and the overall AUC is notincreased.CONCLUSION: While intact PE UV endo lack sustained Ca2� bursts invivo, PE derived HUVEC maintained in vitro do show both restoredCa2� bursting and increased frequency relative to control. Any suchrecovery of function in vitro suggests there was indeed a suppressionof function by local factors in vivo. Further, since PE derived HUVECmanifest sustained Ca2� burst responses which are both more rapidand of reduced size relative to control HUVEC, this suggests cell sig-naling programming is also altered relative to control. Funded by NIHGrant R21HD069181.

Poster Session V Academic Issues, Antepartum Fetal Assessment, Genetics, Hypertension, Medical-Surgical-Disease www.AJOG.org

S338 American Journal of Obstetrics & Gynecology Supplement to JANUARY 2012