Influence of Depigmenting Chemical Agents on Hair and Skin Color in Yellow (Pheomelanic) and Black (Eumelanic) Mice

The study investigated the effects of depigmenting agents on hair and skin color in yellow (pheomelanic) and black (eumelanic) mice. Topical applications of monobenzylether of hydroquinone (MBEH) and intraperitoneal injections of phenol caused graying of hair in eumelanic mice but had little effect on pheomelanic mice. Amcinonide, an anti-inflammatory agent, caused whitening of some hairs in both types of mice. Phenol-treated eumelanic mice showed damaged follicular melanocytes incorporated into developing hair, while the effects of MBEH and amcinonide on follicular melanocytes were not clearly determined. The tail skin of both eumelanic and pheomelanic mice was not depigmented by phenol or MBEH, although MBEH stimulated melanocyte activity. Amcinonide reduced the number of DOPA-positive epidermal melanocytes in the tails, negatively affecting the tail epidermis, with partial reversal by MBEH but not by prostaglandin (PGE2).