Define the Mechanism of Hormone Action

Hormones affect cell function either by activating cyclic AMP (Adenosine monophosphate) mechanism or by activating genes. You may recall reading about the cyclic AMP mechanism in the Nutritional Biochemistry Course. Here, you will find a brief explanation of the mechanism. In the cyclic AMP mechanism, the activating hormone combines with a specific receptor substance on the surface of the cell membrane.

This activates the enzyme adenyl cyclase in the membrane, which in turn converts some of the adenosine tri- phosphate (ATP) inside the cell into cyclic adenosine monophosphate (cyclic AMP). This substance has an activating effect on many intracellular reactions.