Differences in Activity of Minoxidil and Cyclosporin A on Hair Growth in Nude and Normal Mice: Comparisons of In Vivo and In Vitro Studies

The study compared the effects of minoxidil and cyclosporin A on hair growth in nude and normal mice. It was found that minoxidil did not affect the cyclic hair growth in nude mice, whether administered topically or orally, and only stimulated hair growth in normal mice follicles in vitro. In contrast, cyclosporin A, when administered orally, increased peak hair growth in nude mice and stimulated growth in their vibrissae follicles in vitro, but not in normal mice. The study concluded that cyclosporin A could compensate for a genetic defect in nude mice follicles, while minoxidil did not address the critical defect in hair growth in these mice. Therefore, nude mice were deemed unsuitable for studying minoxidil effects but potentially useful for exploring the effects of the nude gene on hair growth.