Wibool Ridtitid, Peerati Ruangsang, Wantana Reanmongkol, and Malinee Wongnawa

pp. 1519 - 1526

Abstract

The methanolic extract of Piper sarmentosum Roxb. leaves at doses of 50, 100 and 200 mg/kg was investigated for anti-inflammatory and antipyretic activities on carrageenan-induced rat paw edema and brewer's yeast-induced pyrexia in rats. The results revealed that the extract at test doses produced a significant anti-inflammatory activity at 3 h with an inhibition of paw edema of 8.6% (P<0.05), 18.6% (P<0.01) and 24.7% (P<0.01), respectively, compared to the reference drug aspirin 200 mg/kg p.o. with an inhibition
of 33.3% (P<0.01). Only the extract at the dose of 200 mg/kg p.o. showed a significant inhibition of carrageenan-induced rat paw edema beginning at 2 h of 11.8% (P<0.01) and at 3, 4 and 5 h of 24.7% (P<0.01), 14.1% (P<0.01) and 11.9% (P<0.01), respectively, whereas the reference drug aspirin 200 mg/kg p.o. exhibited a significant inhibition of edema beginning at 1 h of 15.6% (P<0.05) and at 2, 3, 4 and 5 h of 31.8% (P<0.01), 33.3% (P<0.01), 30.4% (P<0.01) and 30.2% (P<0.01), respectively. The methanolic extract of P. sarmentosum leaves (50, 100 and 200 mg/kg p.o.) did not decrease brewerís yeast-induced pyrexia in rats, whereas aspirin at the dose of 200 mg/kg p.o. showed a significant antipyretic activity by reducing fever in
this animal model. In acute toxicity test, the methanolic extract of P. sarmentosum leaves at the dose of 5 g/kg did not produce any abnormal symptoms or mortality in rats.