PROTECTIVE EFFECT OF NIFEDIPINE AGAINST CARRAGEENAN-INDUCED INFLAMMATION

Administration of carrageenan (CA; 0.5 mg) to the plantar tissue of ra ts resulted in reversible inflammatory injury. The edema was monitored by changes in paw volume using a plethysmometer. Simultaneous adminis tration of CA and nifedipine, intraperitoneally, at different doses (1 0, 20 and 50 mg/kg) prevented the inflammatory action, and the effect was dose-and time-dependent. In order to improve the nifedipine effect s, we prepared liposomed nifedipine which, administered intraperitonea lly, showed a greater anti-inflammatory action. In the presence of the L-type channel agonist Bay K 8644, the inflammation produced by CA in creased and it was counteracted by free or liposomed nifedipine. The s ignificance of these findings with respect to the mechanism of the ant i-inflammatory action of nifedipine is discussed.