Recombinant secreted nonpancreatic phospholipase A2 induces a synovitis-like inflammation in the rat air pouch.

Abstract

The aim of this study was to test the proinflammatory action of human secreted phospholipase A2 (sPLA2) in an animal model of synovitis-like inflammation and to compare it with a Group 1 (porcine pancreatic) and a Group 2 (Naja mocambique mocambique) PLA2. The subcutaneous injection of air in the rat pouch induced the formation of a connective tissue cavity lined with cells closely resembling a synovium. sPLA2 (0.01-10 micrograms/pouch) porcine pancreatic (10 micrograms/pouch), PLA2 or Naja mocambique mocambique PLA2 (10 micrograms/pouch) were injected in a 6-day rat air pouch. Our data show that recombinant human enzyme PLA2 (0.01-10 micrograms/pouch), but not Naja mocambique mocambique (Group 2 PLA2) and porcine pancreatic PLA2 (Group 1 PLA2), was able to exacerbate the inflammatory response without increasing eicosanoid release. Only sPLA2 was able to exacerbate rat air pouch and its effect was unrelated to eicosanoid release.