Feedback regulation of basal pancreatic secretion in humans

The effect of intrajejunal infusion of pancreatic juice on basal pancreatic secretion was studied in patients who had received pancreatoduodenectomy for pancreatic, biliary, or duodenal malignancy. Pure pancreatic juice was obtained through a drainage tube inserted into the main pancreatic duct. There was little fibrosis in the pancreatic remnant and daily pancreatic juice output was more than 200 ml. After intraluminal infusion of pancreatic juice, water, protein, bicarbonate, and enzyme outputs were decreased significantly by about 30%. Intraluminal trypsin also reduced pancreatic secretion. Trypsin inhibitor (aprotinin) suppressed the significant decrease caused by autopancreatic juice or trypsin solution. We conclude that basal pancreatic secretion in humans is under negative feedback control by intestinal pancreatic juice or tryptic activity.