hormones which affect the generation of cyclic 3′,5′-AMP, also influence the release of pancreatic insulin 1–5 have led us to examine the effect of this cyclic nucleotide on insulin secretion.

The cyclic nucleotide phosphodiesterase 4 (PDE4) regulates the hydrolysis of the second messenger cyclic AMP. cAMP is a major intracellular signalling mediator that directly affects the activity ...