PHOSPHOLIPASE-A2 IN SODIUM TAUROCHOLATE-INDUCED EXPERIMENTAL HEMORRHAGIC-PANCREATITIS IN THE RAT

We investigated the concentration of immunoreactive pancreatic phospho lipase A2 (pan-PLA2) and the catalytic activity of phospholipase A2 (C A-PLA2) in plasma, peritoneal fluid, and pancreas of rats in which acu te hemorrhagic pancreatitis was induced by an intraductal injection of sodium taurocholate. The contribution of pancreas to the CA-PLA2 in p lasma was studied by removing pancreatic PLA2 by absorbing plasma samp les with a polyclonal antibody raised in a rabbit against rat pancreat ic PLA2. Sodium taurocholate injected into the pancreatic duct produce d hemorrhagic pancreatitis with necrosis and inflammatory cell invasio n within 8 hr. Saline injection caused edematous pancreatitis, but sha m operation did not alter pancreatic morphology from normal. The conce ntration of pan-PLA2 increased rapidly in plasma in all animals, but s ignificantly more in sodium taurocholate-injected animals than in sali ne-injected or sham-operated animals. The level of CA-PLA2 in plasma i ncreased in sodium taurocholate-injected animals only. There was no co rrelation between pan-PLA2 and CA-PLA2 values in plasma in sodium taur ocholate-injected animals. The CA-PLA2 was marginally increased in pan creatic tissue of sodium taurocholate-injected animals compared to tha t of saline-injected and sham-operated animals at 8 hr. Treatment by t he anti-pan-PLA2 antibody effectively removed pan-PLA2 from plasma and peritoneal fluid samples in sodium taurocholate-injected animals. The level of CA-PLA2 in plasma was similar before and after antibody trea tment. It was concluded that the concentrations of pancreatic PLA2 and the catalytic activity of PLA2 increase in rat plasma during experime ntal hemorrhagic acute pancreatitis. The catalytically active PLA2 in plasma is derived from a nonpancreatic source(s). (C) 1995 Academic Pr ess, Inc.