The Effect of Propranolol on Insulin-stimulated Gastric Secretion in Dogs

The effect of beta-adrenergic blockade on the insulin hypoglycemia-induced gastric secretion was studied. Insulin-stimulated (0.15 IU/kg) gastric acid and pepsin output and serum gastrin were measured before and during beta-adrenergic blockade with propranolol (20 μg/kg/min intravenous infusion) in gastric fistula and Heidenhain pouch dogs. Insulin injection caused acid and pepsin secretion from the gastric fistula, and both acid and pepsin secretion was significantly increased during beta-adrenergic blockade. Significant gastrin release was observed after insulin stimulation. However, the insulin-induced gastrin release was unaltered by intravenous infusion of propranolol. The Heidenhain pouch did not show any secretion in these experiments. It is concluded that beta-adrenergic blockade augments the hypoglycemia-induced gastric secretion in dogs. Furthermore, it seems that this effect is not dependent on vagally released gastrin.