Schenken R S, Williams R F, Hodgen G D
Department of Obstetrics and Gynecology, University of Texas Health Science Center, San Antonio 78284.
Fertil Steril. 1990 Dec;54(6):1146-9. doi: 10.1016/s0015-0282(16)54019-9.
Progestins facilitate estrogen induction of the preovulatory luteinizing hormone (LH) surge. A biologically weaker progestin, 20 alpha-dihydroxyprogesterone, is reportedly increased at midcycle, but the importance of 20 alpha-dihydroxyprogesterone in regulating LH release has not been systematically studied. We therefore evaluated the effect of 2 doses of 20 alpha-dihydroxyprogesterone on the bioactive LH surge onset in ovariectomized monkeys. Chronically cannulated monkeys (n = 10) received estradiol (E2) benzoate (50 micrograms/kg) with and without subsequent 20 alpha-dihydroxyprogesterone injections (50 micrograms/kg, n = 3 and 100 micrograms/kg, n = 3). Blood was collected every 15 minutes over preselected intervals and the plasma assayed for bioactive LH and gonadal steroids. Low-dose 20 alpha-dihydroxyprogesterone administration resulted in periovulatory peripheral 20 alpha-dihydroxyprogesterone levels and did not advance the bioactive LH surge onset. In contrast, high-dose 20 alpha-dihydroxyprogesterone resulted in supraphysiological 20 alpha-dihydroxyprogesterone levels, slight increases in progesterone levels, and significant advancement of the surge over E2 benzoate treatment alone. We conclude that periovulatory levels of 20 alpha-dihydroxyprogesterone do not play a role in modulating the estrogen-induced bioactive LH surge.
孕激素可促进雌激素诱导的排卵前促黄体生成素（LH）峰。据报道，一种生物活性较弱的孕激素，20α-二羟孕酮，在月经周期中期会增加，但20α-二羟孕酮在调节LH释放中的重要性尚未得到系统研究。因此，我们评估了2个剂量的20α-二羟孕酮对去卵巢猴子生物活性LH峰起始的影响。长期插管的猴子（n = 10）接受苯甲酸雌二醇（E2）（50微克/千克），分别在注射和不注射随后的20α-二羟孕酮（50微克/千克，n = 3；100微克/千克，n = 3）的情况下。在预先选定的时间段内每15分钟采集一次血液，并检测血浆中的生物活性LH和性腺甾体。低剂量注射20α-二羟孕酮导致围排卵期外周血20α-二羟孕酮水平升高，但并未提前生物活性LH峰的起始时间。相比之下，高剂量20α-二羟孕酮导致20α-二羟孕酮水平超过生理水平，孕酮水平略有升高，且与单独使用苯甲酸雌二醇治疗相比，峰明显提前。我们得出结论，围排卵期的20α-二羟孕酮水平在调节雌激素诱导的生物活性LH峰中不起作用。
