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 investiga ted the distribution of PLA2 protein by immunohistochemistry and the distri bution of mRNA of PLA2 by Northern blotting and in situ hybridization in ra t tissues. PLA2 protein was localized in the Paneth cells of the intestinal mucosa, chondrocytes and the matrix of cartilage, and megakaryocytes in th e spleen. By Northern blotting, mRNA of PLA2 was found in the gastrointesti nal 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 oth er 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 hyb ridization of mRNA of rat PLA2) will provide useful tools for future studie s concerning the role of PLA2 in various experimental disease models.