Enzymatic modulation of hormonal action at the target tissue.
Enzymatic modulation of hormonal action at the target tissue.
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靶组织荷尔蒙作用的酶调节。
DOI：
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发表时间：
1978
期刊：
影响因子：
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通讯作者：
E. Gurpide
中科院分区：
文献类型：
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作者：
E. Gurpide
讨论了靶组织中类固醇代谢与激素作用的相关性。考虑了细胞水平代谢调节的两种机制：从类固醇前激素形成活性类固醇，以及活性化合物向无活性代谢物的受控转化。提到了调节活性激素和非活性代谢物之间的相互转化优先进行的方向的因素；描述了估计体外和体内优选方向的方法并给出了示例。人类子宫内膜中的雌二醇-雌酮系统用于描述一种情况，其中激素（黄体酮）诱导酶活性（17β-羟基类固醇脱氢酶），并通过增加活性激素（雌二醇）向无活性或活性较低的代谢物（雌酮）的转化来降低细胞内/细胞外的活性激素（雌二醇）浓度比。已发表的人类子宫内膜中雌二醇的数据表明，激素代谢可以有效地确定可与受体结合的未结合激素的水平，使用结合结合方程和米氏方程的动力学分析。
The relevance of metabolism of steroids in target tissues to hormonal action is discussed. Two mechanisms of metabolic regulation at the cellular level are considered: formation of active steroids from steroidal prehormones, and controlled conversion of the active compound to inactive metabolites. Factors regulating the direction in which interconversions between active hormones and inactive metabolites preferentially proceed are mentioned; methods of estimating the preferred direction in vitro and in vivo are described and examples are given. The estradiol-estrone system in human endometrium is used to describe a case in which a hormone (progesterone) induces an enzymatic activity (17 beta-hydroxysteroid dehydrogenase) and lowers the intracellular/extracellular ratio of concentrations of the active hormone (estradiol) by increasing its conversion to an inactive, or less active, metabolite (estrone). That hormone metabolism can effectively determine the level of unbound hormone available for association to receptors is shown with published data on estradiol in human endometrium, using a kinetic analysis in which binding and Michaelis-Menten equations are combined.