Glycogen in Skin of the Mouse During Cycles of Hair Growth

Summary

During telogen, anagen I, and anagen II no glycogen is present in the hair follicle except for occasional granules in the capsule. Glycogen begins to appear in the lower external sheath in anagen III and persists in large quantities in this layer during the period of hair production. In addition, glycogen is found in the unkeratinized cuticle of the hair shaft and medulla in anagen IV through VI. Glycogen disappears abruptly from all these structures during catagen. Skin has 2 to 3 times as much glycogen during periods of hair growth than it has during telogen or at three days after plucking (anagen stages preceding hair growth). Cytochemical data indicate that this increase is due largely to the increased amount of glycogen found in the external sheath during periods of active hair production.