Question

Explain mechanism of hormone action through membrane receptor.

Answer 1

1. The endocrine system controls body activities by means of chemical messengers called hormones. Hormones are released directly into the blood.
2. Hormones like catecholamines, peptide and polypeptide hormones are not lipid soluble. Therefore they cannot enter their target cells through plasma membrane.
3. These non steroid water soluble hormones interact with surface receptor, which initiate metabolic activity.
4. Molecules of amino acid derivatives, peptide hormones bind to specific receptor molecules located on the plasma membrane.
5. The hormone receptor complex causes the release of an enzyme adenylate cyclase from the receptor site. This enzyme forms cyclic AMP from ATP of the cell. cAMP activates enzymatic actions.