Evidence for a defective inhibition of pentagastrin-stimulated gastric acid secretion by antral distension in the duodenal ulcer patient.

Graded antrum distension by 50-, 100-, and 150-ml balloon volumes significantly stimulated gastric acid secretion in 6 duodenal ulcer patients, but had no stimulatory effect in 6 healthy subjects. Antrum distension by 150-ml balloon volume had no effect on the acid response to submaximal stimulation by a continuous intravenous infusion of pentagastrin in the duodenal ulcer patients, but significantly inhibited this response in the healthy subjects. The inhibition by antrum distension in the healthy subjects amounted to 20%. The results suggest that antrum distension elicits stimulatory as well as inhibitory mechanisms in man with inhibition of acid secretion predominating in healthy subjects and stimulation of acid secretion predominating in duodenal ulcer patients. The mechanism of inhibition is unknown.