Rao M C, Richards J S, Midgley A R, Reichert L E
Endocrinology. 1977 Aug;101(2):512-23. doi: 10.1210/endo-101-2-512.
In association with luteinization, LH induces a decrease in the content of receptors for FSH and LH and an increase in that for PRL. To elucidate if the mechanism by which LH regulates its own receptors involved occupancy of sites and/or loss of receptors the effects of a luteinizing dose of LH were examined in the preovulatory follicles of immature hypophysectomized rats primed with estradiol and FSH. The measurable LH receptor content declined by 82% 24 h after LH administration. Serum concentration of the hormone declined by 24 h to 1.4% of the concentration measured 2 h after LH administration. Administration of iodinated LH to demonstrate occupancy of sites in vivo, resulted in a decline in the amount of hormone bound in vivo, over a period of time. This decline in occupancy paralleled the decrease in the number of available sites as measured in vitro. Furthermore, a large dose of highly purified hFSH administered in lieu of LH induced luteinization and an associated loss of gonadotropin receptors. These results indicate that luteinizing doses of LH and FSH induce a loss in gonadotropin receptors by mechanisms other than occupancy.
与黄体化相关，促黄体生成素（LH）可使促卵泡生成素（FSH）和LH的受体含量降低，而使催乳素（PRL）的受体含量增加。为了阐明LH调节自身受体的机制是否涉及位点占据和/或受体丢失，在经雌二醇和FSH预处理的未成熟垂体切除大鼠的排卵前卵泡中，研究了黄体化剂量的LH的作用。给予LH后24小时，可测量的LH受体含量下降了82%。激素的血清浓度在24小时后降至LH给药后2小时测量浓度的1.4%。给予碘化LH以证明体内位点的占据情况，结果在一段时间内，体内结合的激素量下降。这种占据情况的下降与体外测量的可用位点数量的减少平行。此外，用大剂量高度纯化的人FSH替代LH给药可诱导黄体化，并伴有促性腺激素受体的丢失。这些结果表明，黄体化剂量的LH和FSH通过位点占据以外的机制诱导促性腺激素受体的丢失。
