HORMONAL REGULATION OF MYOCARDIAL ADENOSINE 3',5'-MONOPHOSPHATE

A simple, sensitive, and specific method for measuring changes in adenosine 3′,5′-monophosphate (cyclic AMP) has been applied to the investigation of hormonal control of myocardial cyclic AMP in the rat ventricular slice. Catecholamines have been demonstrated to produce a 100% increase in cyclic AMP levels. Insulin had no effect on cyclic AMP levels and did not alter the catecholamine-induced rise. The presence of Ca2+ in the extracellular fluid was not essential for the production of cyclic AMP, nor was it required for the catecholamine-induced rise in cyclic AMP. Neither glucagon, triiodothyronine or ouabain had any significant effect on cyclic AMP levels in the rat-heart slice. © 1969.