Effects of selective gastric vagotomy and pyloroplasty on oral and intravenous glucose tolerance and insulin secretion.

In peripheral and portal venous blood, the immunoreactive insulin (IRI) and glucose levels in response to orally and intravenously administered glucose were measured in 14 patients with selective gastric vagotomy and pyloroplasty (SGV+P) and in 17 control subjects with other abdominal surgery. After intravenously administered glucose, the insulin and the glucose levels were nearly identical in both groups. After orally administered glucose, there were remarkable differences. Despite their early postoperative situations, and in contrast to the control patients, the SGV+P subjects showed no hyperglycemia. The measurements of IRI in the portal vein suggested that in SGV+P patients, the response of the islet cells is accelerated. In patients with SGV+P, the release of an insulinotropic intestinal factor and the preserved vagal innervation of the pancreas may be responsible for the accelerated insulin response of the undisturbed glucose tolerance.