Specific beta-adrenergic mechanisms in the hypoglycaemic activation of gastrin and gastric acid secretion.

To study whether specific beta-adrenergic mechanisms contribute to the hypoglycaemic activation of gastrin and gastric acid secretion, the effects of racemic and dextroisomer propranolol (0.1 mg/kg, intravenously) were studied during insulin tests (0.2 IU/kg) in 13 persons. dl-Propranolol inhibited the gastrin response to hypoglycaemia markedly and more than the insignificant alteration observed after d-propranolol. Gastric acid response to hypoglycaemia was significantly reduced by dl-propranolol and not by d-propranolol. The findings demonstrate that non-beta-adrenergic effects of propranolol on the stomach are minor and that specific beta-adrenergic mechanisms are directly or indirectly involved in the hypoglycaemic stimulation of the stomach.