STUDIES ON THE METABOLISM OF C19 STEROIDS IN RAT LIVER. 6. HYDROXYLATION OF 4-ANDROSTENE-3,17-DIONE IN RAT LIVER MICROSOMES

Abstract

Following incubations of androstenedione with 105 000 × g microsomes of adult male rat liver, 6β-, 6α-, 7α-, 16α-, and 18-hydroxyandrostenedione were isolated by thin-layer chromatography and identified by gas chromatography-mass spectrometry. After incubations with testosterone the only 3,17-dioxo-Δ⁴-steroids formed were 6β- and 7α-hydroxyandrostenedione. 6β- and 18-Hydroxyandrostenedione were isolated after incubations with 6β- and 18-hydroxytestosterone, respectively. The relative importance of the 17-oxo- and the 17β-hydroxy-pathways in the formation of 3,17-dioxo-Δ⁴-C₁₉O₃ steroids is discussed.