Cellular interrelationships of the outer root sheath of the hair follicle

The 3H-thymidine labelling has demonstrated that into the internal (accompanying) layer of the outer root sheath (ORS) of the hain follicle the cells incorporate not only in the bulb but above it from the external layers of the ORS. Polymorphism of the ORS cells has been revealed electron microscopically; it can be interpreted as a result of transfer of some motionless, greatly vacuolized, containing a lot of glycogen cells to the cells with electron opaque cytoplasm, radially elongated and moving deep into up to their contact with the internal root sheath. The presence in the external layer of the ORS, at the level of the bulb and above it, some nonlabelled cells even 3 days after 3H-thymidine administration demonstrates against their origin from the cambial cells.