Role of gastrointestinal hormones in the response to massive resection of the small bowel.

Hypersecretion of gastric acid and accelerated intestinal transit are largely unexplained consequences of massive resection of the small bowel; several postulated humoral mechanisms remain unsubstantiated. The purpose of the study was to investigate the effects of 75% resection of the distal small bowel in dogs on circulating levels of a range of gastrointestinal hormones. Basal and meal-stimulated concentrations of insulin, secretin, gastrin, pancreatic glucagon, and total glucagon-like immunoreactivity (GLI) were measured by radioimmunoassay techniques. After resection, significant depletions of basal and stimulated total GLI (p less than 0.05 -- p less than 0.001) and a significant rise of stimulated gastrin (p less than 0.05) were discovered. These hormonal alterations may produce an important imbalance of humoral influences on gastrointestinal function. It is suggested that these changes may hold a key to the aetiology of the complications of massive resection of the small bowel.