Effects of pancreaticobiliary duct obstruction on the exocrine and endocrine rat pancreas.

Experimentally, biliary obstruction can produce morphological and functional changes in the pancreatic gland, whereas pancreatic obstruction may have short-term (hyperamylasemia, pancreatic edema, and lysosomal hydrolase redistribution) or long-term (acinar cell atrophy and interstitial fibrosis) effects. We created a pancreaticobiliary duct obstruction in rats to evaluate (a) exocrine and endocrine anatomobiochemical pancreatic modifications; (b) structural and functional liver alterations; and (c) the relationship, if any, between the alterations found in the two organs. Forty-five male Sprague-Dawley rats were subdivided on the basis of period of obstruction (from 1 to 28 days). In each rat serum we evaluated amylase, cholestatic and cytolytic indices, and glucose. In frozen pancreatic samples we measured insulin, glucagon, and DNA; in the liver the DNA content was determined. Histologically, ductal dilation and proliferation were evaluated for the liver, zymogen granules, and Langerhans' islets, and atrophy for the pancreas. Fibrosis was evaluated for both the liver and the pancreas. Short-term common pancreaticobiliary duct ligation caused an increase in serum amylase levels and mild pancreatic edema. Longer-term obstruction had either similar or different effects on the two organs. In the pancreas it caused fibrosis and exocrine and endocrine atrophy, but not acute pancreatitis. In the liver the main phenomena observed were fibrosis, ductal dilation, and proliferation.