Effect of Propranolol on Pentagastrin-Induced HCl Secretion and Gastric Mucosal Blood Flow in Dogs

Abstract Dogs with Heidenhain pouch and vagally innervated gastric fistula were given continuous intravenous infusion of pentagastrin (1.2 μg per kg-hr) and aminopyrine (5 mg per kg-hr). The steady state volume, acid concentration, and output from the pouch and the fistula were significantly augmented for 1 to 21/2 hr by 0.5 mg per kg of propranolol, the β-adrenergic blocker. The mucosal clearance of plasma aminopyrine was increased while the ratio of aminopyrine concentration in the gastric juice to that in the plasma was decreased by propranolol. Propranolol augmented secretion of the Heidenhain pouch more than that of the vagally innervated gastric fistula. Although the augmented gastric response was accompanied by an increased gastric mucosal blood flow, the results suggest that the change in blood flow was not the primary mechanism responsible for the augmentation.