Manifestations of experimental acute pancreatitis in young and old rats

Two kinds of experimental pancreatitis were induced in young (4-6 month) and old (25-27 month) female Wistar rats: acute edematous pancreatitis was induced by intraperitoneal administration of a high dose of cerulein (40 micro/kg x 2) and acute hemorrhagic pancreatitis was intraductal injection of 1% deoxycholic acid. After these treatments, the plasma amylase concentration and pancreatic wet weight were determined and the pancreas was examined histologically. In the groups with cerulein induced pancreatitis one of eight old rats died, whereas all five young rats survived. There was no specific finding macroscopically in the liver, kidney, lung or heart of old rats at autopsy after cerulein injection. The plasma amylase concentration and the pancreatic wet weight were significantly increased by administration of cerulein or deoxycholic acid in both young and old rats. There was no significant difference in the plasma amylase concentrations in young and old rats after the induction of acute pancreatitis. The increase in pancreatic wet weight was less in old rats than in young ones after deoxycholic acid treatment, but similar in the two groups after cerulein injection. The extents of histological changes were also similar in young and old rats. Thus, no evidence that aging increases susceptibility to pancreatitis was obtained.