Mekanisme Kerja Hormon
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Transcript of Mekanisme Kerja Hormon
Mekanisme Kerja Hormon
dr. Susila Sastri M.BiomedBiokimia FK-Unand
Hormone
Struktur Kimia Hormon
1. Polipeptida• Insulin• Glucagon
2. Derivat asam amino (amin)• Epineprin• Serotonin• Tyroxin
3. Steroid (derivat kolesterol)• Aldosteron• Cortisol• Retinoic acid
4. Eicosanoid (polyunsaturated • acid, (20atom C)
• Prostadglandin E• Thromboxane A2
Simple Intracellular & Extracelluler Signaling
Hormon Action
Hypophise Anterior
Neurohormone
GAS MOLECULE
Cell Communication
Second messenger:
Small molecules synthesized in cells in response to an external signal are the second messengers, which are responsible for intracellular signal transduction:
Ca2+, DG, Cer, IP3, cAMP, cGMP
Receptor Receptors: specific membrane proteins,
which are able to recognize and bind to corresponding ligand molecules, become activated, and transduce signal to next signaling molecules:
A. Membran
B. Intra Sel
Glycoprotein or Lipoprotein
HypothalamusAnterior pituitary Posterior pituitary
Thyrotropin
ACTH
Somatotropin
LH
FSHProlactin
Vasopressin
Oxytocin
ThyroidAdrenalCortex
AdrenalMedullaPancreas Ovary Testis
Muscles liver Tissues
Liver,muscles
Estradiol TestosteroneInsulin,glucagon,somatostatin
T3 Cortisolaldosterone
Mammary glands
Reproductive organs
Epinephrine
Releasinghormones
Nervous
Kelenjer-Hormon-Target Sel
1. Membrane receptors
Signal transduction mediated by membrane receptor
• cAMP dependent-protein kinase A pathway
• cGMP dependent PKG pathway • Ca2+ dependent PK pathway • Tyrosine protein Kinase pathway
• NF-κB pathway • TGF- βpathway
Membrane Receptor
Cyclic AMP
Mekanisme Signal Tranduksi
Glucagon
Cyclic AMP Cyclic GMP Ca2+ Diacylgycerol Proteinsubstrates
PK-A PK-G Calmodulin PK-C Protein Ser/Thr kinases
Protein substrates
Protein substrates
Protein substratesMultifunctional kinases
Otherphospholipases
1 2 3 4 5
11 2 3 4 5
Tyrosine kinase
IP3G G G G
Insulin T-cellActivation
Nitricoxide
G protein
End result is phosphorylation ofone or more proteins
Hormon-2nd Massengger- Enzim
Inositol triphosphate System
PLC; phospholipase CPIP2: phosphoinositolDAG:diacylgliserolIP3:inositol triphosphatPKC: phosphokinase C
Intracellular receptor (DNA transcription regulated
receptor)
Steroid Hormone, VD3, Thyroxine
• Cytosolic R: glycocorticosteroid H
• Nuclear R: thyroxine, estrogen, androgen, progesterone
Hormon - Receptor
• highly specificity
• highly affinity
• saturation
• reversible binding
• special function model
Control of receptor activity
• Phosphorylation or dephosphorylation of R
• Phospholipid of membrane
• Enzyme catalyzed hydrolysis
• G protein regulation
Thyroid Mechanism of Action
Adrenaline Mechanism of action
ACTH Mechanism of Action
Aldosteron Mechanism of Action
Estrogen Mechanism of Action
Androgen Mechanism of Action
Insulin Receptor
Insulin Action
Glucagon
GH/ STH
hormons: glucagon, epinephrine
inactive AC active AC
ATP cAMP
inactive PKA active PKA
phosphorylase b kinase
phosphorylase b kinase
P
ATP
ADP
H2O
Pi
phosphorylase b
P
P
ATP ADP
Pi
H2OATP ADP
glycogen synthase
glycogen synthase
P
H2OPi protein phosphatase-1
(active) (inactive)
inhibitor-1 (active)
inhibitor-1 (inactive)
phosphorylase a
ATP