ANDROGEN METABOLISM IN THE VENTRAL SEBACEOUS GLAND PATCH OF THE MONGOLIAN GERBIL

SUMMARY The metabolism of [7α-3H]dehydroepiandrosterone (DHA), [7α-3H]-androstenedione and [7α-3H]testosterone was studied in the ventral sebaceous gland patch of the Mongolian gerbil in vitro. The main enzyme activities found were 17β-hydroxysteroid dehydrogenase, 5α-reductase, 17α-hydroxysteroid dehydrogenase, 3α-hydroxysteroid dehydrogenase, sulphotransferase and hydroxylase. The active androgen 5α-dihydrotestosterone was formed in appreciable amounts from both testosterone and androstenedione. The 17β-hydroxysteroid dehydrogenase actively formed both 17-oxo and 17β-hydroxysteroids in this tissue. The conversion of DHA to C4–5 unsaturated steroids and 5α-steroids was not observed presumably due to a lack of 3β-hydroxysteroid dehydrogenase Δ4–5isomerase. The metabolism was compared with that in human and rat skin and its significance discussed.