Smirnov A N, Shchelkunova T A, Rozen V B
Biokhimiia. 1986 May;51(5):751-3.
The relative competitive activity of some androstane derivatives was determined by 50% inhibition of [3H]estradiol binding to an unusual estrogen-binding protein (UEBP) of male rat liver. It was shown that: i) the bulk of energy of the steroid-protein complex is derived from hydrophobic interactions; ii) the authentic ability to form specific complexes with UEBP at androgene concentrations close to physiological ones, is determined by 17 beta-hydroxyl and is enhanced by the 3 alpha- or 2 alpha-oxy-group; iii) 3- and 17-keto groups inhibit androgene interaction with UEBP; iiii) the cis-conjunction of rings A and B in the androgen molecule does not block steroid binding to the protein. These data specify significantly the mechanism of androgene interaction with UEBP and shed additional light on the physiological role of this protein.
通过抑制[3H]雌二醇与雄性大鼠肝脏中一种特殊雌激素结合蛋白（UEBP）的结合达50%，来测定某些雄甾烷衍生物的相对竞争活性。结果表明：i）类固醇 - 蛋白质复合物的大部分能量来自疏水相互作用；ii）在接近生理浓度的雄激素浓度下与UEBP形成特异性复合物的真实能力，由17β - 羟基决定，并因3α - 或2α - 氧基而增强；iii）3 - 和17 - 酮基抑制雄激素与UEBP的相互作用；iiii）雄激素分子中环A和B的顺式连接并不阻碍类固醇与该蛋白质的结合。这些数据显著明确了雄激素与UEBP相互作用的机制，并进一步揭示了该蛋白质的生理作用。
