Effects of Fundic Distention on Pentagastrin-Stimulated Gastric Acid Secretion in Man

The acid secretory effect of combined stimulation with balloon distention of the fundus and body of the stomach and intravenous infusion of pentagastrin has been studied in patients with duodenal ulcer (DU) and in healthy subjects. In 8 nonoperated DU subjects and in 5 DU patients subjected to proximal gastric vagotomy, low grade fundic distention moderately enhanced the acid output evoked by a threshold dose of pentagastrin. Fundic distention with a balloon volume eliciting a maximal acid response to distention either left unchanged or suppressed the maximal acid secretory rate produced by pentagastrin in 7 nonoperated and 6 vagotomized DU patients and in 5 healthy subjects. The heterogeneous secretory effects of maximal stimulus combination suggest that fundic distention has a complex action on acid secretion eliciting a hitherto unknown inhibitory effect as well as a cholinergic activation of the parietal cell area. This complex action may explain the failure of fundic distention to augment markedly the action of pentagastrin in the present study.