Chakraborty C, Sen M, Johnson D C
Department of Gynecology and Obstetrics, Ralph L. Smith Research Center, University of Kansas Medical Center, Kansas City 66103.
Proc Soc Exp Biol Med. 1988 Nov;189(2):189-95. doi: 10.3181/00379727-189-42796.
Using high-performance liquid chromatography and a combination of electrochemical and radiometric flow detection for 2-[14C]hydroxyestradiol, changes in estrogen 2-hydroxylase activity in the microsomal fraction of rat ovarian homogenates were followed. Injection of human chorionic gonadotropin (hCG) at 12-hr intervals to hypophysectomized immature rats stimulated hypertrophy of the theca-interstitial tissue and produced a profound increase in enzyme activity. With the last injection of hCG at 96 hr the peak serum concentration of hCG was reached 12 hr later and then decreased exponentially with a half-time of 13 hr. However, enzyme activity remained elevated for at least 60 hr before beginning to fall. Pregnant mare's serum gonadotropin (PMSG) also produced an increase in activity, which was apparently limited to the thecal-interstitial tissue because freshly removed granulosa cells from the mature follicles had undetectable activity levels. Administration of anti-PMSG antiserum after enzyme activity had been increased resulted in a prompt fall in activity, as did injection of hCG to mimic an ovulatory surge of LH. The results indicate that the thecal-interstitial tissue of the rat ovary has estrogen 2-hydroxylase activity that is dependent upon gonadotropic stimulation for expression.
使用高效液相色谱法以及电化学和放射性流动检测相结合的方法对2-[¹⁴C]羟基雌二醇进行检测，追踪大鼠卵巢匀浆微粒体部分中雌激素2-羟化酶活性的变化。对垂体切除的未成熟大鼠每隔12小时注射人绒毛膜促性腺激素（hCG），刺激卵泡膜间质组织肥大，并使酶活性大幅增加。在96小时时最后一次注射hCG，12小时后达到hCG血清峰值浓度，然后以13小时的半衰期呈指数下降。然而，酶活性在开始下降前至少保持升高60小时。孕马血清促性腺激素（PMSG）也使活性增加，这显然仅限于卵泡膜间质组织，因为从成熟卵泡中新鲜分离的颗粒细胞的活性水平检测不到。在酶活性增加后给予抗PMSG抗血清，活性迅速下降，注射hCG模拟促黄体生成素（LH）的排卵高峰时也是如此。结果表明，大鼠卵巢的卵泡膜间质组织具有雌激素2-羟化酶活性，其表达依赖于促性腺激素刺激。
