Additional evidence of acute anti-inflammatory effects of cyclosporin A in a murine model of pleurisy.

INTRODUCTION

It is well known that cyclosporin A (CsA) exhibits important anti-inflammatory effects, besides its immunosuppressive activity. However, the mechanisms by which CsA exerts these effects remain unclear.

OBJECTIVE

This study evaluated whether the acute administration of CsA significantly interfered in leukocyte migration, exudation, myeloperoxidase (MPO) and adenosine-deaminase activities and nitrate/nitrite levels, in a mouse model of pleurisy.

MATERIALS AND METHODS

Pleurisy was induced by carrageenan (1%) treatment and the parameters were analyzed 4 and 48 h after. Groups of animals were previously treated with different doses of CsA and compared with non-treated groups.

RESULTS

CsA (0.1-5 mg/kg, intraperitoneal, 1 h before pleurisy induction) inhibited neutrophil migration (P<0.05), but not the exudation that occurred 4 h after pleurisy induction. At this time, CsA (1 mg/kg, 1 h before) also decreased nitrate/nitrite levels and MPO activity (P<0.01). CsA (2 mg/kg, 0.5 h before) was also effective in decreasing mononuclear influx, exudation and nitrate/nitrite levels 48 h after onset of inflammation.

CONCLUSIONS

These results indicate that the acute administration of CsA is able to reduce the two leukocyte populations that occur both at 4 and 48 h after pleurisy induction, late exudation (48 h), MPO activity (4 h) and nitrate/nitrite levels (4 and 48 h). Taken together, these findings indicate that CsA has acute anti-inflammatory effects in immunocompetent animals.