Histamine receptors in unstimulated pancreatic exocrine secretion of the rabbit

Histamine H2-receptor antagonists cimetidine and oxmetidine, H2-receptor agonist dimaprit, H1-receptor antagonist chlorpheniramine and H1-receptor agonist 2-thiazolylethylamine were tested for their effects on unstimulated pancreatic exocrine secretion in anaesthetized rabbits fitted with an acute pancreatic cannula. Intravenous administration of H1 agonist induces a dose-dependent increase in pancreatic secretion but H1 antagonist have the opposite effects. Intravenous administration of H2 antagonists induces effects similar the ones produced after H1 agonist infusion. The implications of H1 and H2 receptors on exocrine pancreatic secretion are discussed.