title: [Early observations of pancreatic ultrastructure during hemorrhagic necrosis in the rat with closed duodenal pouch].
abstract: Many problems are still unanswered in the pathogenesis of acute clinical and experimental pancreatic necrosis. A new technique which can be performed in the rat seems a suitable model for reflux pancreatic necrosis without artificial pressure changes in the ductal system. A closed duodenal loop is obtained with ligation proximal and distal to Vater's ampulla and a gastroenteroanastomosis is associated to avoid intestinal obstruction. All the rats die with hemorrhagic pancreatic necrosis in 36 hours. After 12 hours from the operation ductal and acinar lumina are enlarged. In the centroacinar and intercalated duct cells some lysosomes and mitochondria with clear matrix and reduced cristae are detected. Intercellular junctions in ducts and acini have normal morphology. In the basal cytoplasm of acinar cells some prominent autophagic vacuoles are detectable. After 24 hours in the acinar cells autophagic vacuoles are greatly increased and basal cytoplasmic degeneration often occurs, with plasmalemma and basal lamina interruptions. Intercellular junctions are apparently unaffected until cell necrosis sets in. In blood capillaries endothelial cells are swollen, fibrin thrombosis, hemorrhage and leucocyte infiltration are often detectable. As lysosomal activity occurs also in different kinds of experimental pancreatic necrosis, it could be a common pathogenetic factor, responsible for hydrolytic enzyme activation and for vascular damage in the early stages of hemorrhagic pancreatic necrosis.
mesh_terms: D000818:Animals; D004386:Duodenum; D006471:Gastrointestinal Hemorrhage / Q000473:pathology*; D008297:Male; D009336:Necrosis; D010179:Pancreas / Q000473:pathology* / Q000648:ultrastructure; D051381:Rats
vernacular_title: Prime osservazioni ultrastrutturali sulla necrosi emorragica del pancreas nel ratto con tasca duodenale chiusa.