Acetylation and hydroxylation of 5alpha-androstane-3beta,17beta-diol by prostate and epididymis

An unknown radiometabolite, formed in the canine prostate and epididymis after intra-arterial infusion of testosterone-4-¹⁴C in physiologic saline and extraction of the organs with ethyl acetate-acetone, was identified as the 3-monoacetate of 5α-androstane-3β, 17β-diol (3β-diol). Transformation of 3β-diol-¹⁴C to its identified 3-monoacetate derivative could also be demonstrated, if the incubation of the radiosubstrate with minced canine prostate was terminated by ethyl acetate extraction. The formation of polar products in high yield was noted. Whereas minced canine prostate actively converted 5α-androstane-3α,17β-diol-¹⁴C to 17β-hydroxy-5α-androstan-3-one-¹⁴C, the same preparation hydroxylated 3β-diol-¹⁴C predominantly at the 7ξ- and, to a lesser extent, at the 6ξ-positions. Partial identification of the hydroxylated radiometabolites was by crystallization of the CrO₃-oxidation products 5α-androstane-3,6,17-trione-¹⁴C and 5α-androstane-3,7,17-trione-¹⁴C to constant SA and by GLC/MS of the latter derivative. NADPH-supplementation of the preparation enhanced the yield of hydroxylated products derived from 3β-diol-¹⁴C in a 1 hr incubation from 22% to 41%. Analogous supplemented incubations of benign hyperplastic human prostate and canine epididymis produced polar metabolites (in 12.5% and 76% yields, respectively) which gave rise to similar proportions of the same androstanetrione epimers on CrO₃-oxidation.