Gut and Pancreatic Hormones after Jejunoileal Bypass with 3:1 or 1:3 Jejunoileal Ratio

Abstract

The differential role of the jejunum and ileum in the regulation of secretion of the gut hormones, gastrin, gastric inhibitory polypeptide [GIP] and enteroglucagon and the pancreatic hormones, insulin, glucagon and pancreatic polypeptide [PP], was elucidated in man. The plasma levels of the hormones (and glucose) were measured during fasting and after a test meal in 34 obese patients, of whom 5 were waiting for bypass surgery and 29 had had a jejunoileal bypass with a 3:1 or 1:3 jejunoileal ratio between the functioning segments 3, 9 or 15 mo. earlier. The major findings were that bypass surgery has no important influence on the levels of gastrin and PP, reduces the level of GIP, insulin (and glucose) and enhances the pancreatic glucagon level, independently of the jejunoileal ratio and increases enteroglucagon secretion, most effectively so with a short jejunal and long ileal segment left in continuity. The upper jejunum and terminal ileum probably has no important role in regulation of secretion of these hormones apart from that in secretion of enteroglucagon which is related to the length of functioning ileum.