Abstract: Objective To study the effect of minoxidil on the growth of hair follicles.Methods Organ cuhure of new-born mouse vibrissa follicles in vitro.incorportating of ³H-TdR radioaetive thymidine into the cultured follieles and the histopathologic features of the follicles.Results When the the follieles were eultured in 701μg/ml of minoxidil for 24h.the follicles had a signifieanl inerease in length, the hair dermal papilla loosned. the follicle bulb enlarged, and the matrix cells grew actively, when cultured for 48h.Ihe rate of increase of the length of the follicles reduced.When cultured for 30h.there was a signfieant increase of ³H-TdR incorporating. Conclusion The results indieate thai minoxidil promotes the growth of hair follicles, and is related to its CODcentration and the duration of culture of the follieles.

Key words: Minoxidil, Hair, Tissue culture