Inhibition of rat paw oedema and pleurisy by the extract from Mandevilla velutina

Abstract

This study reports the oral anti-inflammatory profile of the crude extract (CE) of Mandevilla velutina, a plant which has been previously demonstrated to selectively antagonize bradykinin response of the isolated tissues on rat paw oedema and pleurisy caused by different phlogistic agents. The CE (50 to 200 mg/kg), given 60 min before, inhibited in a dose-dependent manner bradykinin (BK) and cellulose sulphate-induced paw oedema, maximal inhibition of 59% and 65%, respectively. In the same range dose the CE also significantly antagonized pleural exudate and cell infiltration caused by these substances, maximal inhibition of 34% and 46%, respectively. In addition, the CE (100 and 200 mg/kg) also inhibited paw oedema induced by serotonin, PAF-acether and zymosan, maximal inhibition of 55%, 38% and 46%, respectively, but enhanced histamine oedema. However, the CE revealed only partial or no inhibition in pleural exudate caused by these agents. The CE (100 and 200 mg/kg) also inhibited in a dose and time-dependent manner carrageenan-induced paw oedema with a maximal inhibition of 44%, but only partially affected carrageenan-induced pleural exudate. The CE also partially inhibited dextran oedema, but even at a higher dose (400 mg/kg) it failed to interfere with Bothrops Jaracaca-induced paw oedema. The CE inhibited BK and to a lesser extent cellulose sulphate-induced cell migration, but failed to interfere with the differential leukocyte migration in the pleural cavity. These findings provide evidence that the CE from M. velutina, besides antagonizing kinin action, exhibit an oral anti-oedematogenic activity against a variety of phologistic agents, but it was more effective in inhibiting those models where kinins are more involved.