Acute necrotizing pancreatitis caused by the injection of lysolecithin into the pancreatic duct in the rat. Its natural course and effect of drugs on rate of survival

: Acute experimental pancreatitis was induced by retrograde injection of 0.15 ml of 0.8% lysolecithin into the pancreatic duct of Wistar rats. This procedure was always followed by severe necrosis of pancreatic parenchyma, bloody ascites and numerous fat necroses in the abdominal cavity. Histologically, at the 30th minutes after the induction of pancreatitis, spotty necrosis of pancreatic tissues and marked edema of interstitium were observed. The necrosis gradually expanded accompanying bleeding and inflammatory cell infiltration till the 60th hours. At the 72nd hours after the induction there were the replacement of the necrotic tissue with the fibroblasts, the neogenesis of the ductular epithelium and the formation of acinus-like structure. Among the changes of extrapancreatic organs those of the lung were pronounced. Macroscopically, from the 12th hours stiff and reddish lung frequently occurred. Histologically, micro-macroatelectasis, edema and cell infiltration of the alveolar wall, and the stricture of the bronchioles were observed. In this experimental pancreatitis, the rate of survival was about 50% within 48 hours and about 30% within 72 hours, respectively. Continuous intravenous infusion of cytidine diphosphate choline at a dose of 300 mg/kg/day and intravenous injection of methylprednisolone at a dose of 60 mg/kg/day significantly improved the rate of survival within 24 hours and within 30 hours, respectively.