Conversion of dihydrotestosterone to androstanediol glucuronide by female sexual skin.

Sexual skin biopsies from 13 normal women were obtained and minces/3-h studied after adding either [3H]dihydrotestosterone (DHT) or [3H]androstanediol (3 alpha diol) to RPMI-1640 medium in a Dubnoff apparatus. Unconjugated or conjugated androgens (after hydrolysis) were purified by three chromatography steps. Formation of 3 alpha diol and 3 alpha diol glucuronide (3 alpha diolG) was linear with time. The conversion of DHT to DHT17 beta G was only 4.4 +/- 0.5%/200 mg/3 h, while conversion to 3 alpha diol was 32 +/- 1.7%. The back conversion of 3 alpha diol to DHT was 30 +/- 3% and conversion to 3 alpha diolG was 4.5 +/- 1.25%. The product of the conversion separately measured of DHT to 3 alpha diol and 3 alpha diol to 3 alpha diolG was 1.5%, which is not very different than the overall conversion rate of DHT to 3 alpha diolG of 1.4%. This study indicates that the predominant path in this tissue is DHT in equilibrium 3 alpha diol----3 alpha diolG, rather than formation of DHT17 beta G and then 3 alpha reduction to 3 alpha diolG.