Effects of ethanol metabolism on oxidoreduction and intermolecular hydrogen transfer at C-17 in steroid 3-sulphates in vivo.

Steroid sulphates were infused intravenously in female rats, and metabolites were isolated from bile. Infused 3 beta-hydroxy-5 alpha-androstan-17-one 3-sulphate was excreted together with 5 alpha-androstane-3 beta,17 beta-diol disulphate, which formed a large part after ethanol administration. Results from infusions of the 3-sulphates of 5 alpha-[17 alpha-2H]androstane-2 beta,17 beta-diol and 3 beta-hydroxy-5 alpha-[2,2,4,4-2H4]androstan-17-one indicated that ethanol decreased the extent of transfer of the 17 alpha-deuterium and increased the reduction of 17-oxosteroid without affecting the oxidation of 17 beta-hydroxysteroid. Ethanol metabolism decreased the deuterium transfer from [17 alpha-2H]estradiol 3-sulphate to C-17 of 3 beta-hydroxy-5 alpha-androstan-17-one 3-sulphate. The results indicate that NADH from ethanol metabolism increased the concentration of oxidoreductase-NADH complex without affecting the corresponding complex with NAD+. The effects of ethanol on steroid reduction were dependent on the initial redox state of the enzyme-coenzyme complex. This redox state was modified by substrates for the enzyme, indicating slow dissociation of the complex. Thus, ethanol metabolism may interfere with the interactions between steroid oxidoreductions.