SURGICAL TRAUMA INDUCES GROUP-II PHOSPHOLIPASE-A2 PRODUCTION BY NEUTROPHILS AT A LOCAL SITE AFTER SURGERY

Objectives: Group II phospholipase A2 (PLA2) regulates eicosanoids and platelet activating factor (PAF) production and plays an important ro le in regulating critical mediators in inflammatory diseases such as t rauma, sepsis and multiple organ failure. To elucidate the local effec t of surgical trauma, we investigated the production of group II PLA2 at a local site after surgery. Design and methods: We utilized a radio immunoassay to measure group II PLA2 levels in peritoneal exudates fro m the operative field and blood in patients who underwent gastrectomy. We also investigated the production of group II PLA2 in cells from pe ritoneal exudates by Northern blotting and immunocytochemistry.Results : immunoreactive group II PLA2 levels were significantly increased fro m 3 h after surgery and peaked at 12 h in peritoneal exudates. However , serum group II PLA2 levels peaked at 24-48 h and decreased gradually after surgery, findings similar to levels of postoperative serum C-re active protein (CRP). There was no significant correlation between gro up II PLA2 levels in peritoneal exudates and those in blood. Group II FLAP mRNA was expressed at high level in cells from peritoneal exudate s, by Northern blot analysis, but not those from blood. The localizati on of group II PLA2 protein was intense in neutrophils, as determined by immunocytochemistry. No group II PLA2 expression was observed in co rresponding peripheral blood cells. Conclusions: After surgery, group II PLA2 is increased in peritoneal exudates prior to elevation in the blood circulation and is produced by neutrophils recruited and activat ed at a local site. Group II PLA2 produced in peritoneal exudates by n eutrophils has an important role in the physiological and pathological states at a local site, after surgery. Copyright (C) 1998 The Canadia n Society of Clinical Chemists.