EFFECTS OF LEUKOCYTE AND PLATELET DEPLETION ON ISCHEMIA - REPERFUSION INJURY TO DOG PANCREAS

Background/Aims: Ischemia-reperfusion injury has been studied in various organs. Effects of leukocyte and platelet depletion on ischemia-reperfusion injury were evaluated using the isolated, perfused dog pancreas in vivo. Methods: Pancreatic exocrine and endocrine functions were stimulated by an intra-arterial injection of cholecystokinin (10(-12) mol) and intravenous injection of glucose and arginine (1 g/kg body wt), respectively. The functions before and after 60 minutes of ischemia were evaluated in the no treatment and in the leukocyte and platelet depletion groups. Results: Cholecystokinin increased prostaglandin I-2 and thromboxane A(2) production and stimulated exocrine pancreatic secretion. Glucose and arginine stimulated insulin and glucagon release from the pancreas. Sixty minutes of ischemia followed by 60 minutes of reperfusion damaged the pancreatic acinar and ductular cells. Ischemia of 60 minutes followed by 90 minutes of reperfusion damaged beta cells. Removal of leukocytes (97.6%) and platelets (99.4%) by using a filter throughout the experiment prevented the ischemia-reperfusion injury, reduced plasma lipid peroxide and thromboxane A(2), and increased prostaglandin I-2 levels. Conclusions: Leukocytes and platelets seem to damage the pancreas during ischemia-reperfusion by increasing the peroxidation of structurally important cell membrane lipids and reduced the thromboxane A(2) prostaglandin I-2 ratio, a predictor of cellular injury.