Gielen J E, Van Cantfort J, Kremers P
Arch Toxicol. 1976 Dec 17;36(3-4):255-66. doi: 10.1007/BF00340533.
Two microsomal steroid hydroxylase activities (cholesterol-7alpha-hydroxylase and progesterone-16alpha-hydroxylase) were measured in the livers of Sprague-Dawley and Wistar rats and compared to three other monooxygenase activities (aryl hydrocarbon hydroxylase, p-nitro-anisole-O-demethylase and aminopyrine-N-demethylase). Cholesterol-7alpha-hydroxylase behaves in a very unique manner. It is the only one of the studied enzymes to be more active in the female than in the male, it is very poorly induced by phenobarbital and methylcholanthrene, but responds quickly to the administration of glucocorticoids. In fact, the cholesterol-7alpha-hydroxylase activity presents a very pronounced circadian rhythm which is under the control of the hypothalamo-adrenal axis. Marked differences are also found in the response of the various enzymatic activities to the administration of inducers as well as in their relative activities in untreated male and female animals.
在斯普拉格 - 道利大鼠和Wistar大鼠的肝脏中测定了两种微粒体类固醇羟化酶活性（胆固醇7α - 羟化酶和孕酮16α - 羟化酶），并与其他三种单加氧酶活性（芳烃羟化酶、对硝基苯甲醚O - 脱甲基酶和氨基比林N - 脱甲基酶）进行了比较。胆固醇7α - 羟化酶表现出非常独特的方式。它是所研究的酶中唯一在雌性中比在雄性中更活跃的酶，它很少受苯巴比妥和甲基胆蒽诱导，但对糖皮质激素的给药反应迅速。事实上，胆固醇7α - 羟化酶活性呈现出非常明显的昼夜节律，该节律受下丘脑 - 肾上腺轴的控制。在各种酶活性对诱导剂给药的反应以及它们在未处理的雄性和雌性动物中的相对活性方面也发现了显著差异。
