Basic concepts of the mechanism of action of peptide hormones

Abstract

The diverse effects of peptide and protein hormones upon their target cells are now recognized to be mediated by a series of biochemical events which link the primary site of peptide hormone action, the plasma membrane, with a variety of target cell responses. These include synthesis of specific regulatory proteins, stimulation of carbohydrate and lipid metabolism, altered cell permeability and ion transport, and secretion or release of target cell products such as steroid and peptide hormones. A common feature of hormonal molecules which are derived from aminoacid precursors, such as transmitter agents and peptide hormones, is their ability to combine with specific receptor sites in the plasma membrane of their target cells. Occupancy of such membrane receptors is followed by rapid activation of individual cellular responses, ranging from altered permeability to secretory processes and cell growth.