Role of Cyclic AMP in Hormone Actions

THE biologic role of cyclic AMP (adenosine 3′,5′-monophosphate), at least as it is understood today, is shown in Figure 1. After release from an endocrine gland, a hormone is transported to its effector cell, where it interacts, and the inter action ultimately has a measurable physiologic effect. The interactions of several hormones with their target cells have been shown to result in the activation of a membrane enzyme system called adenyl cyclase, which catalyzes the transformation of adenosine triphosphate (ATP) to cyclic AMP. The increased cyclic AMP, acting intracellularly, then carries out the work of the hormone by affecting the activities . . .