Sheets J J, Estabrook R W
Biochemistry. 1985 Nov 5;24(23):6591-7. doi: 10.1021/bi00344a043.
To investigate the potential interaction of the various pathways of androgen hydroxylation, we have conducted studies to identify the profile of products formed during the time course of metabolism of androst-4-ene-3,17-dione (AD). Incubates containing AD, NADPH, and liver microsomes (from rats pretreated with phenobarbital) were sampled at times between 0 and 20 min and the metabolites resolved by reverse-phase (C18) high-performance liquid chromatography. By this method, the pattern of formation and of utilization of eight major primary and secondary metabolites of AD was determined. We report here the formation of two previously unidentified major metabolites of AD: 6 beta,16 alpha-dihydroxyandrost-4-ene-3,17-dione and 6 beta,16 beta-dihydroxyandrost-4-ene-3,17-dione. We propose that liver microsomal cytochromes P-450 can sequentially hydroxylate a single molecule of AD at multiple sites. These hydroxylase activities are presumably a result of multiple cytochrome P-450 isozymes acting on AD resulting in a transient time course for the appearance of some monohydroxylated metabolites. In addition, a unidirectional conversion of the metabolite 16 alpha-hydroxyandrost-4-ene-3,17-dione to 16 beta-hydroxyandrost-4-ene-3,17-dione is described. Evidence is provided to support the role of cytochrome P-450 in catalyzing this reaction.
为了研究雄激素羟基化各种途径之间的潜在相互作用，我们开展了多项研究，以确定雄甾-4-烯-3,17-二酮（AD）代谢过程中形成的产物谱。含有AD、NADPH和肝微粒体（来自用苯巴比妥预处理的大鼠）的孵育物在0至20分钟之间的不同时间点取样，代谢产物通过反相（C18）高效液相色谱法分离。通过这种方法，确定了AD的八种主要初级和次级代谢产物的形成和利用模式。我们在此报告AD的两种先前未鉴定的主要代谢产物的形成：6β,16α-二羟基雄甾-4-烯-3,17-二酮和6β,16β-二羟基雄甾-4-烯-3,17-二酮。我们提出肝微粒体细胞色素P-450可以在多个位点对单个AD分子进行顺序羟基化。这些羟化酶活性可能是多种细胞色素P-450同工酶作用于AD的结果，导致一些单羟基化代谢产物的出现具有短暂的时间进程。此外，还描述了代谢产物16α-羟基雄甾-4-烯-3,17-二酮向16β-羟基雄甾-4-烯-3,17-二酮的单向转化。提供了证据支持细胞色素P-450在催化该反应中的作用。
