Splenic and gastro-duodenal vein occlusion--influence on the pancreatic gland and on the outcome of experimental pancreatitis.

The observation that splenic vein thrombosis results in pancreatic changes similar to haemorrhagic pancreatitis initiated the present investigation. The influence of splenic and/or gastroduodenal vein occlusion on the pancreatic gland was evaluated and compared to that obtained after induction of experimental pancreatitis (EP). The influence of splenic vein occlusion on EP was also investigated. An approximately 4-fold increase in serum amylase activity was obtained after simultaneous ligation of the splenic and gastroduodenal veins. This increase was comparable to that obtained after EP. On the other hand, amylase activity in ascites was considerably lower after vein occlusion than after EP. Splenic vein occlusion in rats with EP more moderately increased the amylase activity but did not influence mortality rate 24 h postoperatively. Venous thromboses were observed in all groups with occluded veins but not in rats with EP. Vein occlusion alone did not result in fat necroses. Although occlusion of the splenic and gastroduodenal veins results in macromorphologic and biochemical changes resembling those in EP, the microscopic findings of the two conditions differ. Thus, the results do not support the hypothesis that pancreatic vein thromboses are of etiologic significance for the development of acute haemorrhagic pancreatitis.