RESUMO
Seeds of Abrus precatorius L., Fabaceae, are commonly used as purgative, emetic, aphrodisiac and in nervous disorder in traditional and folk medicines. In present study petroleum ether and ethanolic extracts of A. precatorius seeds are evaluated for reversal of androgen (testosterone by i.m route) induced alopecia in male albino wistar rats and compared to topical administration of standard antiandrogenic drug finasteride for 21 days. The results were reflected from visual observation and histological study of several skin sections via various parameters as anagen to telogen ratio and follicle density/mm area of skin surface. The animal of group 1 who were treated with only testosterone became alopecic on visual observation. Animals of Group 2, 3 and 4 who were treated with finasteride, petroleum ether and ethanolic extract of seed respectively topically along with testosterone (i.m) did not developed alopecia. To investigate the mechanism of observed activity, in vitro experiments were performed. Inhibition of 5α-reductase activity by extracts and finasteride suggest that they reversed androgen induced alopecia by inhibiting conversion of testosterone to dihydrotestosterone (potent androgen responsible for androgenic alopecia). So it may be concluded that petroleum ether and ethanolic extract of A. precatorius seed posses anti androgenic alopecia activity due to inhibition of 5α-reductase enzyme.