HAIR FOLLICLE ELONGATION IN ORGAN-CULTURE OF SKIN FROM NEWBORN AND ADULT MICE

By means of skin organ culture, some biological characteristics of hai r follicle elongation were examined. When skin sections from 6-day-old C3H mice were cultured, spontaneous elongation of hair follicles was maintained. Without insulin, hair follicle elongation was poorly maint ained irrespective of the presence of serum at 20%. Insulin could be r eplaced by IGF-I at 100 ng/ml. During in vitro elongation of hair foll icles, bromodeoxyuridine was incorporated into germinal epithelial cel ls around dermal papillae. Skin sections from 4-week-old C3H mice did not show hair follicle elongation in complete medium. However, when 0. 5 mM minoxidil was added to the medium, concentration dependent thicke ning and elongation of hair follicles was observed. In contrast, in vi tro elongation of newborn pelage hair follicles was not enhanced by mi noxidil. These results suggest that this system with the use of skill sections from 4-week-old C3H mice would be a potential in vitro model of human androgenic alopecia in which the anagen phase is suppressed b ut the suppression is partially released by minoxidil. (C) 1998 Elsevi er Science Ireland Ltd. All rights reserved.