1. Signalling mechanism of hormones Dr. Sadaf Mumtaz 27-1-11

3. Broad Classification (Structure) Hydrophillic Lipophillic Proteins, peptide hormones & catecholamines Steroid and thyroid hormones Primarily act through second messenger system Activate genes on binding with receptors in the nucleus Circulate mainly dissolved in the plasma Largely bound to plasma proteins

6. Location for different types of hormone receptors

9. Onset of hormone secretion and action

11. Cyclic variations

13. Mechanism of activation of GPCRs

14. Enzyme linked hormone receptors

15. Second messenger mechanisms

16. ER SOC TRPC1,4 IP3R RhoA-GTP RhoGDI-P Rhokinase MLC-P ROC TRPC3,6,7 Ca 2+ calmodulin Ca 2+ CaM CamKinase II Inactive MLCK Active MLCK Phosphorylation MLC Dephosphorylation MLCP Inactive Phosphorylated MLCP (PP1c-MYPT1) GPCR RTK Agonist PLC PIP2 DAG IP3 Ca 2+ PKC Ca 2+ CP1-17 CP1-17-P PP2A MT dissassembly Actin polymerization Stress fibre formation Activation mechanism of ECs MLCP

19. Radioimmunoassay Antibody Fluid from animal containing hormone + + (Hormone + Radioisotope) Competition for antibody binding Equilibrium Antibody complex separated Quantity of radioactive hormone complex is measured by radioactive counting technique

20. ELISA

22. Pituitary hormones and its control by hypothalamus

23. Hypothalamic releasing and inhibiting hormones control anterior pituitary secretion TRH GnRH CRH GHRH GHIH PIH

26. Thank you