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Mekanisme Kerja Hormon. dr. Susila Sastri M.Biomed Biokimia FK- Unand. Hormone. Struktur Kimia Hormon. Polipeptida Insulin Glucagon Derivat asam amino ( amin ) Epineprin Serotonin Tyroxin. 3. Steroid ( derivat kolesterol ) Aldosteron Cortisol Retinoic acid
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Mekanisme Kerja Hormon dr. SusilaSastriM.Biomed Biokimia FK-Unand
Struktur Kimia Hormon • Polipeptida • Insulin • Glucagon • Derivatasam amino (amin) • Epineprin • Serotonin • Tyroxin • 3. Steroid (derivatkolesterol) • Aldosteron • Cortisol • Retinoic acid • 4. Eicosanoid (polyunsaturated • acid, (20atom C) • Prostadglandin E • Thromboxane A2
Cell Communication GAS MOLECULE
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
Kelenjer-Hormon-Target Sel Hypothalamus Nervous Releasing hormones Anterior pituitary Posterior pituitary Thyrotropin Somatotropin FSH Vasopressin Prolactin LH Oxytocin ACTH Adrenal Cortex Adrenal Medulla Thyroid Pancreas Ovary Testis Cortisol aldosterone Insulin, glucagon, somatostatin Estradiol Testosterone T3 Epinephrine Reproductive organs Muscles liver Liver, muscles Mammary glands Tissues
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
1 2 3 4 5 Hormon-2nd Massengger- Enzim Nitric oxide T-cell Activation Glucagon Insulin 1 3 4 5 2 G G G IP3 G Tyrosine kinase G protein Protein substrates Cyclic GMP Ca2+ Diacylgycerol Cyclic AMP Calmodulin PK-C PK-A PK-G Protein Ser/Thr kinases Protein substrates Protein substrates Multifunctional kinases End result is phosphorylation of one or more proteins Other phospholipases Protein substrates
Inositol triphosphate System PLC; phospholipase C PIP2: phosphoinositol DAG:diacylgliserol IP3:inositol triphosphat PKC: 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