IN-VITRO STEROIDOGENESIS BY GONADS OF THE RUSSIAN STURGEON, ACIPENSERGUELDENSTAEDTI BRANDT

Ovaries and testes from the Russian sturgeon at different stages of se xual maturity were incubated with H-3-androstenedione or H-3-pregnenol one. The major metabolites of androstenedione in both sexes were testo sterone and 5 alpha- and 5 beta-androstanediols, but no evidence was f ound for the gonadal production of 11-oxygenated androgens. Pregnenolo ne was converted to 17-hydroxyprogesterone, androstenedione and testos terone together with reduced metabolites. 11-Oxygenated androgens were found in female serum by gas chromatography-mass spectrometry (GC-MS) , in serum of both sexes by radioimmunoassay (RIA), and was detectable by RIA in interrenal but not gonadal tissue. The results suggest that sturgeon may differ from teleosts in that 11-oxygenation may take pla ce in extragonadal tissues.