The Effect of Minoxidil on Human Hair Growth In Vitro

The study investigated the effects of minoxidil on human hair follicles in vitro, using hair follicle culture and 3H-TdR incorporation. It was found that minoxidil at concentrations of 0.05 mmol/L, 0.1 mmol/L, and 0.5 mmol/L significantly promoted hair follicle growth, resulting in longer and faster growth compared to control follicles. These concentrations also delayed the transition to the catagen phase. However, at a higher concentration of 2 mmol/L, minoxidil inhibited hair follicle growth, leading to shorter and slower growth than controls. The study concluded that minoxidil could enhance hair follicle growth at lower concentrations but had an inhibitory effect at higher concentrations.