Characterization of receptors for gastrointestinal peptides.

Acinar cells from guinea pig pancreas possess six different classes of receptors that mediate the actions of various secretagogues on enzyme secretion. Two classes of receptors stimulate enzyme secretion by causing activation of adenylate cyclase and increased cellular cyclic AMP; four classes of receptors stimulate enzyme secretion by causing mobilization of cellular calcium. This paper summarizes the results of studies that have employed radiolabeled secretagogues of high specific activity and have measured directly the interaction of secretagogues with their receptors on pancreatic acinar cells.