The metabolism of testosterone by human male scalp skin.

Abstract

SUMMARY [4-14C]Testosterone was incubated with human male scalp skin and the metabolites identified as 5α-androstane-3α, 17β-diol, androsterone, epiandrosterone, dihydrotestosterone, androstenedione and androstanedione. A metabolite not previously reported from incubations of human skin with androgens was isolated and is probably a steroid ester. One bald and one hairy scalp biopsy specimen from each of five subjects were incubated with [4-14C]testosterone for 1 h and the radioactivity of each metabolite was measured after separation by thin-layer chromatography. Both the uptake and metabolism of testosterone were greater in bald skin than in hairy skin. Little difference in the percentage of each metabolite in the total metabolite pool was found between bald and hairy skin from the same subject and skin from different subjects. This demonstrated that male pattern baldness was not accompanied by gross changes in testosterone metabolism. The main finding was that bald skin contained increased amounts of 5α-reduced metabolites.