Effects of proximal gastric vagotomy on gastric secretory and plasma hormonal responses to sham feeding in patients with duodenal ulcers.

The effects of proximal gastric vagotomy on the gastric secretion of acid and pepsin, and on the release of gastrin and pancreatic polypeptide in response to sham feeding were assessed comparatively within 1-4 months after surgery in 32 male duodenal ulcer patients. Each test comprised three successive periods: basal, modified sham feeding (MSF) and pentagastrin stimulation. In each test period the acid output was strongly correlated with the corresponding pepsin output, both parameters being reduced to similar extents after vagotomy. The percentage of postoperative reduction of MSF-induced acid and pepsin outputs was positively correlated with the preoperative values. MSF resulted in a limited but significant release of gastrin, the response being significantly greater after surgery. The MSF-induced release of pancreatic polypeptide was significantly reduced by proximal gastric vagotomy, the reduction percentage being negatively correlated with the time elapsed since surgery. Neither pre- nor post-operatively did the gastrin and pancreatic polypeptide responses bear any relationship to the other parameters tested. We conclude that the study of sham feeding responses of pepsin, gastrin and pancreatic polypeptide provides no further information than does the measurement of acid secretion for the segregation of duodenal ulcer patients, especially with respect to follow-ups for ulcer recurrence.