The effect of vagotomy on the inhibition of gastric secretion by intraduodenal acid

Abstract

Abstract Acid in the duodenum is known to inhibit gastric secretion in man but whether this response is a humoral or a vagal phenomenon is unknown. If a vagal reflex is involved then selective and highly selective vagotomy, by preserving the duodenal nerve supply, could offer advantages over truncal division. This study was designed to investigate this claim. The effect of intraduodenal hydrochloric acid on pentagnstrin-stimulated gastric secretion was stimulated in 17 control subjects, 32 preoperative duodenal ulcer patients and 28 vagotomized patients (16 truncal vagotomy and pyloroplasty; 6 selective vagotomy and pyloroplasty; 6 highly selective vagotomy). Inhibition of acid output occurred in 15 control subjects, and the mean inhibition for the group was 2.68 + 0.39 mEq/10 minutes (P < 0.001). Inhibition occurred in 22 duodenal ulcer patients, and the mean reduction in acid output for the entire group was 2.26 ± 0.46 mEq/l0 minutes (P < 0.001). Intraduodenal acid failed to produce a response in the vagotomized patients irrespective of the presence or absence of a duodenal nerve supply. These results suggest that gastric secretory inhibition by intraduodenal acid is a vagal phenomenon in man; selective and highly selective vagotomy do not appear to carry any particular advantage over truncal section in terms of preserving this response.