The effect of antral distension in healthy subjects on betazole-stimulated gastric acid secretion and the plasma concentration of immunoreactive neurotensin.

Antral distension in seven healthy subjects had the same inhibitory effect, approximately 20% inhibition, on gastric acid secretion stimulated by pentagastrin and betazole (Histalog). The plasma concentration of neurotensin in peripheral venous blood was unchanged during antral distension in healthy subjects. The plasma concentration of neurotensin in portal blood was also unchanged during antral distension in anaesthetized duodenal ulcer patients and in non-ulcer patients. The inhibition of pentagastrin-stimulated gastric acid secretion by balloon distension of the antrum was unchanged by preceding intramuscular injection of metoclopramide. The inhibitory effect of antral distension on gastric acid secretion in healthy subjects does not seem to be mediated by secretin, cholecystokinin, bulbogastrone, neurotensin, or a dopaminergic mechanism.