Effect of bile duct obstruction on pancreatic enzyme secretion and intestinal proteolytic enzyme activity in the rat

The role of bile in regulation of intestinal proteolytic activity in rats was investigated by studying the effects of bile diversion and bile duct obstruction on pancreatic protease secretion and on recovery of protease from the intestine. Diversion of bile and pancreatic juice from the intestine caused a large increase in pancreatic enzyme secretion; replacement of bile partially suppressed this response. Bile duct obstruction resulted (3-4 days postobstruction) in a threefold increase in pancreatic juice chymotrypsin but caused large decreases in intestinal trypsin and chymotrypsin activities and total proteolytic activity. Recovery of pancreatic juice protein (labeled with¹⁴C) from intestinal contents was markedly decreased in bile duct obstruction, indicating a more rapid rate of degradation and absorption of pancreatic juice protein. The evidence suggests that interruption of bile flow results in an accelerated rate of degradation of pancreatic proteolytic enzymes, and that the increase in pancreatic enzyme secretion is an adaptation to decreased intestinal proteolytic activity.