Extrapancreatic multiorgan injury in a severe sublethal acute pancreatitis model

In order to develop a new severe but sublethal acute pancreatitis model for the study of clinically relevant extrapancreatic multiorgan injury, we have induced acute pancreatitis in a rat model by intraductal injection with low dose and moderate concentration of bile acid under low pressure. We examined the structural and functional features in the pancreas, lung, liver and kidney. The animals were divided into two groups: the bile acid injection group and the control group. In the bile acid injection group, acute necrotizing pancreatitis was induced by intraductal administration of 0.2 ml of 2.0% bile acid under 30 cm H2O pressure, while the controls underwent the sham operation. The two groups were divided into six subgroups (8 rats for each) and sacrificed at 12, 24, 36, 48, 72 and 144 h, respectively. The pancreatitis induced hyperamylasemia, ascites, pancreatic oedema, haemorrhage, acinar cell necrosis and extensive fat necrosis without early mortality. Accompanied with the pancreatic injury, the function and histologic changes have developed continuously in the kidney and liver for 72 and 144 h in the bile acid injection animals respectively. No pancreatitis associated pulmonary changes were found. Taking into account the results with the two previously developed models of pancreatitis, we conclude that the extrapancreatic injury in acute pancreatitis is found in the liver, kidney and lung, in that order, depending on the severity of pancreatitis. The present sublethal pancreatitis model, in comparison with the two previously studied acute pancreatitis models, is perfect for pathogenetic and therapeutic study of liver and renal changes in acute necrotizing pancreatitis.