Regioselective progesterone hydroxylation catalyzed by eleven rat hepatic cytochrome P-450 isozymes.
Regioselective progesterone hydroxylation catalyzed by eleven rat hepatic cytochrome P-450 isozymes.
复制标题
由 11 种大鼠肝细胞色素 P-450 同工酶催化的区域选择性孕酮羟基化。
作者：
David C. Swinney;Dene E. Ryan;Paul E. Thomas;Wayne Levin
定量高压液相色谱法分离孕酮和17个真实的单羟基衍生物。利用11种纯化的大鼠肝细胞色素P-450同工酶和8种不同的大鼠肝微粒体制备物的测定来研究孕酮的羟基化。在重组系统中，孕酮最有效地代谢细胞色素P-450 h，其次是P-450 g和P-450 b。鉴定了7种不同的单羟基孕酮代谢物。由11种同工酶中的8种形成的16 α-羟孕酮是由细胞色素P-450 b和P-450 e形成的唯一可检测的代谢物。2 α-羟孕酮几乎完全由细胞色素P-450 h形成，6 α-羟孕酮和7 α-羟孕酮仅由P-450 a形成。孕酮的6 β-羟基化由四种同工酶催化，其中细胞色素P-450 g最有效，15 α-羟基孕酮作为次要代谢产物由细胞色素P-450 g、P-450 h和P-450 i形成。没有同工酶催化黄体酮的17 α-羟化，只有细胞色素P-450 k具有可检测到的21-羟化酶活性。在二月桂酰磷脂酰胆碱（1.6-80 μ M）的存在下，细胞色素P-450 b催化的16 α-羟基化被抑制，而这种磷脂刺激（高达3倍）或对其他纯化同工酶的孕酮代谢没有影响。结合抗体抑制实验的微粒体代谢的结果表明，细胞色素P-450 a和P-450 h是唯一的7 α-和2 α-羟化酶，分别和P-450 k或免疫化学相关的同工酶贡献大于80%的21-羟化酶活性观察到的微粒体从苯巴比妥诱导的大鼠。
Quantitative high-pressure liquid chromatographic assays were developed that separate progesterone and 17 authentic monohydroxylated derivatives. The assays were utilized to investigate the hydroxylation of progesterone by 11 purified rat hepatic cytochrome P-450 isozymes and 8 different rat hepatic microsomal preparations. In a reconstituted system, progesterone was most efficiently metabolized by cytochrome P-450h followed by P-450g and P-450b. Seven different monohydroxylated progesterone metabolites were identified. 16 alpha-Hydroxyprogesterone, formed by 8 of the 11 isozymes, was the only detectable metabolite formed by cytochromes P-450b and P-450e. 2 alpha-Hydroxyprogesterone was formed almost exclusively by cytochrome P-450h, and 6 alpha-hydroxyprogesterone and 7 alpha-hydroxyprogesterone were only formed by P-450a. 6 beta-hydroxylation of progesterone was catalyzed by four isozymes with cytochrome P-450g being the most efficient, and 15 alpha-hydroxyprogesterone was formed as a minor metabolite by cytochromes P-450g, P-450h, and P-450i. None of the isozymes catalyzed 17 alpha-hydroxylation of progesterone, and only cytochrome P-450k had detectable 21-hydroxylase activity. 16 alpha-Hydroxylation catalyzed by cytochrome P-450b was inhibited in the presence of dilauroylphosphatidylcholine (1.6-80 microM), while this phospholipid either stimulated (up to 3-fold) or had no effect on the metabolism of progesterone by the other purified isozymes. Results of microsomal metabolism in conjunction with antibody inhibition experiments indicated that cytochromes P-450a and P-450h were the sole 7 alpha- and 2 alpha-hydroxylases, respectively, and that P-450k or an immunochemically related isozyme contributed greater than 80% of the 21-hydroxylase activity observed in microsomes from phenobarbital-induced rats.
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影响因子：
2.9
作者：
GUENGERICH, FP;DANNAN, GA;KAMINSKY, LS
通讯作者：
KAMINSKY, LS
影响因子：
3.6
作者：
D. Heuman;E. J. Gallagher;J. Barwick;N. Elshourbagy;P. Guzelian
通讯作者：
D. Heuman;E. J. Gallagher;J. Barwick;N. Elshourbagy;P. Guzelian
细胞色素 P-450 在类固醇激素生物合成中的作用。
影响因子：
--
作者：
Hall,PF
通讯作者：
Hall,PF
异烟肼诱导的大鼠肝微粒体细胞色素 P-450 主要形式的表征。
DOI：
--
发表时间：
1985
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Ryan,DE;Ramanathan,L;Iida,S;Thomas,PE;Haniu,M;Shively,JE;Lieber,CS;Levin,W
通讯作者：
Levin,W
来自成年雄性大鼠肝微粒体的三种高度纯化的细胞色素 P-450 的表征。
DOI：
--
发表时间：
1984
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Ryan,DE;Iida,S;Wood,AW;Thomas,PE;Lieber,CS;Levin,W
通讯作者：
Levin,W