Role of histamine receptors in rabbit pancreatic exocrine secretion stimulated by cholecystokinin and secretin.

An investigation was made of the effects of H1 and H2 receptor agonists and antagonists on rabbit pancreatic exocrine secretion stimulated by secretin and cholecystokinin (CCK). The H1 agonist 2-thiazolylethylamine elicited dose-dependent increases in the rate of secretion. Increases in pancreatic juice flow and enzyme output were also noted after H2 antagonist cimetidine. In contrast, the H1 antagonist chlorpheniramine and H2 agonist dimaprit caused reductions in flow and enzyme output. The results suggest that H1 receptors have stimulative effects and H2 receptors have inhibitory effects on exocrine rabbit pancreas.