Khalil M W, Morley P, Glasier M A, Armstrong D T, Lang T
MRC Group in Reproductive Biology, University of Western Ontario, London, Canada.
J Endocrinol. 1989 Feb;120(2):251-60. doi: 10.1677/joe.0.1200251.
The origin and biosynthesis of 4-oestrene-3,17-dione (19-norandrostenedione), a major steroid in porcine ovarian follicular fluid, was investigated by culturing granulosa cells from 4-6 mm follicles of prepubertal gilts with radiolabelled androstenedione and 19-hydroxyandrostenedione. Steroid metabolites were purified by solvent extraction and lipophilic column chromatography, and analysed by C18 reverse-phase high-performance liquid chromatography. 19-Hydroxyandrostenedione, 19-norandrostenedione and oestradiol-17 beta were obtained as major metabolites from androstenedione, while 19-norandrostenedione and oestradiol-17 beta were the major products from 19-hydroxyandrostenedione. Serum alone or serum plus FSH significantly enhanced formation of 19-norandrostenedione and oestradiol-17 beta from each substrate, compared with controls. Micromolar concentrations (1 mumol/l) of 4-hydroxyandrostenedione, an aromatase inhibitor, significantly reduced formation of 19-norandrostenedione and oestradiol-17 beta by granulosa cells cultured with serum and FSH. Formation of 19-norandrostenedione and oestradiol-17 beta from androstenedione and 19-hydroxyandrostenedione was also significantly inhibited by aminoglutethimide phosphate, a cytochrome P-450 inhibitor known to block the conversion of androstenedione to oestrogens. Ketoconazole, an inhibitor of the cytochrome P-450 dependent 17,20-lysase, blocked formation of 19-norandrostenedione and oestradiol-17 beta only at millimolar concentrations. These results suggest that 19-norsteroid and oestrogen formation from C19 aromatizable androgens may share a common or overlapping pathway, and imply that 19-norsteroid and oestrogen synthesis is mediated by cytochrome P-450 dependent enzymes.
通过用放射性标记的雄烯二酮和19-羟基雄烯二酮培养青春期前小母猪4-6毫米卵泡的颗粒细胞，研究了猪卵巢卵泡液中的主要类固醇4-雌烯-3,17-二酮（19-去甲雄烯二酮）的来源和生物合成。类固醇代谢物通过溶剂萃取和亲脂性柱色谱法纯化，并通过C18反相高效液相色谱法进行分析。从雄烯二酮中获得了19-羟基雄烯二酮、19-去甲雄烯二酮和雌二醇-17β作为主要代谢物，而从19-羟基雄烯二酮中获得的主要产物是19-去甲雄烯二酮和雌二醇-17β。与对照组相比，单独的血清或血清加促卵泡素（FSH）显著增强了每种底物生成19-去甲雄烯二酮和雌二醇-17β的能力。微摩尔浓度（1μmol/l）的4-羟基雄烯二酮（一种芳香化酶抑制剂）显著降低了用血清和FSH培养的颗粒细胞生成19-去甲雄烯二酮和雌二醇-17β的能力。磷酸氨基谷氨酰胺（一种已知可阻断雄烯二酮向雌激素转化的细胞色素P-450抑制剂）也显著抑制了雄烯二酮和19-羟基雄烯二酮生成19-去甲雄烯二酮和雌二醇-17β。酮康唑（一种细胞色素P-450依赖性17,20-裂解酶抑制剂）仅在毫摩尔浓度下阻断了19-去甲雄烯二酮和雌二醇-17β的生成。这些结果表明，由C19可芳香化雄激素生成19-去甲类固醇和雌激素可能共享一条共同或重叠的途径，并暗示19-去甲类固醇和雌激素的合成是由细胞色素P-450依赖性酶介导的。
