Stimulation of pancreatic secretion and growth in the rat after feeding cholestyramine

The influence of luminal bile salts on pancreatic growth in rats was studied by feeding cholestyramine, an anion-exchange resin that binds luminal bile salts, and by chronic bile diversion. Cholestyramine given in food stimulated pancreatic growth, increasing both its size and deoxyribonucleic acid content. A dose of 0.5% was ineffective, but feeding 2%, 6%, and 10% cholestyramine (wt/wt) gave the same degree of pancreatic enlargement. Cholestyramine feeding also augmented the stimulation of pancreatic growth as seen after feeding raw soybean flour containing active trypsin inhibitor. Feeding cholestyramine increased both the basal pancreatic secretion and the secretory response to exogenous cholecystokinin. If they were fasted overnight, the pancreatic enzyme content of cholestyramine-fed rats was also increased with an equal increase in both trypsin and lipase activity. However, enzyme content after cholestyramine feeding depended on the duration of the feeding and whether or not the animals were fasted before killing. Chronic bile diversion caused pancreatic growth similar to that seen in cholestyramine-fed animals. It is suggested that the pancreatic enlargement seen after cholestyramine feeding and bile diversion is an adaption to increased secretion similar to that seen after feeding soybean trypsin inhibitor.