[Serum and ascitic phospholipase A2 activities and their heat stabilities in taurocholate induced rat acute pancreatitis].

Serum and ascitic phospholipase A2 (PLA2) activities in rat acute pancreatitis induced by sodium taurocholate (TCA) were investigated with special reference to their heat stabilities and were compared to those in serum of carrageenan induced granuloma in rats. PLA2 activity was measured by previously reported radiochemical method and was separated into two forms, heat stable and labile PLA2, based on the stability to preincubation at 55 degrees C for 5 minutes. While a heat stable PLA2 predominantly increased in ascitic fluid, the elevations of both heat stable and labile PLA2 activities in serum were observed in TCA induced pancreatitis. On the other hand, serum PLA2, which was mainly composed of heat labile form, elevated with the increase of leukocyte count in carrageenan induced granuloma rats. These facts suggested that serum PLA2 activity might increase in acute inflammatory changes other than in pancreatic diseases. And it is assumed that PLA2 derived from extrapancreatic origins as well as pancreatic secretory PLA2 may also contribute to high PLA2 level in acute pancreatitis, because pancreatic secretory PLA2 was generally accepted to be heat stable.