Teloptosis, a turning point in hair shedding biorhythms.

The timing regulation of the hair growth phases is quite complex. We name teloptosis the termination of the telogen phase with hair shedding. The initiation of the next anagen I phase is independent from teloptosis. Both events are triggered by distinct factors. Indeed, teloptosis is the result of the loss of adhesion between cells of the club hair and those of its epithelial envelope. Teloptosis synchronization is perceived as telogen effluvium, related or not to shortening of the anagen phase. Subtle changes leading to early or delayed teloptosis affect hair density. It is possible to distinguish two types of telogen hairs on a trichogram. Those with an epithelial sheath indicate strong binding, suggesting early telogen, whereas the absence of an epithelial sheath indicates loose binding, conveying teloptosis. Copyright 2001 S. Karger AG, Basel