Distribution of group II phospholipase A2 protein and mRNA in rat tissues.

Group II phospholipase A2 (PLA2) is an acute-phase protein and an important component of the host defense against bacteria. In this study we investigated the distribution of PLA2 protein by immunohistochemistry and the distribution of mRNA of PLA2 by Northern blotting and in situ hybridization in rat tissues. PLA2 protein was localized in the Paneth cells of the intestinal mucosa, chondrocytes and the matrix of cartilage, and megakaryocytes in the spleen. By Northern blotting, mRNA of PLA2 was found in the gastrointestinal tract, lung, heart, and spleen. By in situ hybridization, PLA2 mRNA was localized in the Paneth cells of the small intestinal mucosa but in no other cell types. Our results show specific distribution of PLA2 in a limited number of cell types in rat tissues. The reagents developed in this study (the anti-rat PLA2 antibody and probes for Northern blotting and in situ hybridization of mRNA of rat PLA2) will provide useful tools for future studies concerning the role of PLA2 in various experimental disease models.

Lipopolysaccharide induced apoptosis of rat pancreatic acinar cells.

BACKGROUND: Bacterial lipopolysaccharide (LPS) has been proposed to participate in the pathogenesis of pancreatic inflammatory disease. AIMS: This study investigated the role of endotoxaemia in the pathogenesis of pancreatic acinar cell injury. METHODS: Sixty eight male Spraque-Dawley rats were used in the study. Escherichia coli LPS (5 mg/kg) was injected into the peritoneal cavity of the rats. The concentration of pancreatic phospholipase A2 (PLA2) in plasma was measured and pancreatic tissue examined by histology, in situ detection of free DNA 3'-ends, and electrophoretic DNA analysis. RESULTS: The concentration of pancreatic PLA2 increased in plasma and the catalytic activity of PLA2 increased in pancreatic tissue after an LPS injection. Apoptosis in pancreatic acinar cells and fragmentation of DNA typical of apoptosis in pancreatic tissue was seen 24 hours after an LPS injection. Pancreatic acinar atrophy was seen 72 hours after the LPS injection. CONCLUSIONS: These data show that LPS causes release of pancreatic PLA2 into blood plasma, activation of PLA2 in pancreatic tissue, and apoptosis of acinar cells.

Serum phospholipase A2 in patients with multiple organ failure.

Multiple organ failure (MOF) is the most common cause of death in the surgical intensive care unit. We studied the relation of MOF to changes in the concentration of group II phospholipase A2 (PLA2) in serum. Altogether, 215 surgical intensive care patients with multiple injuries, diffuse peritonitis, or sepsis and control patients, who were at a high risk for postoperative sepsis after various surgical interventions, were included in the present prospective study. The clinical performance of the MOF score and the concentrations of group II PLA2 and C-reactive protein (CRP) in serum were studied using receiver operating characteristic (ROC) curves. The group II PLA2 level was considerably above normal in all groups of patients during the first week of observation. There was a highly significant difference in group II PLA2 levels between patients with severe infections (peritonitis and sepsis) and the other patients studied (multiple injuries and elective surgery) (ROC 0.931, P < 0.0001). The concentration of group II PLA2 had a significant positive correlation to the CRP level and body temperature, which indicates that group II PLA2 is an acute phase reactant and that the determination of group II PLA2 is a useful measurement to diagnose severe infections. It was concluded that the concentration of group II PLA2 in serum effectively predicts lethal MOF in patients with multiple injuries after the second day (ROC 0.739, P < 0.01) and in patients with diffuse peritonitis after the fourth day (ROC 0.750, P < 0.02).