Gershengorn M C, Marcus-Samuels B E, Geras E
Endocrinology. 1979 Jul;105(1):171-6. doi: 10.1210/endo-105-1-171.
The number of plasma membrane receptors for TRH on tumor-derived mammotropic cells in culture, GH3 and GC cells, but not their affinity for TRH, was increased by estrogens. For GH3 cells, exposure to 10 nM 17 beta-estradiol for 48 h increased the receptor level from 54,000 to 90,000 sites/cell, while for GC cells, the number of receptors increased from 29,000 to 46,000 after 28 h. PRL accumulation in the medium was also increased by 17 beta-estradiol. 17 beta-Estradiol and diethylstilbestrol were equally potent in increasing the TRH receptor level, while estrone was only 1/10th as potent. Diethylstilbestrol bound to the cytoplasmic estrogen receptor with an apparent affinity approximately 2.5 times higher than 17 beta-estradiol in GH3 and GC cells, while the affinity for estrone was only 1/12th to 1/20th that of 17 beta-estradiol. Tamoxifen, an antiestrogenic compound, inhibited the increase in TRH receptor number induced by 0.3 nM 17 beta-estradiol and was capable of binding to the estrogen receptor. Modulation of the TRH receptor level on mammotropic cells by estrogens, which is likely mediated through cytoplasmic estrogen receptors, may be an important mechanism for regulation of TRH action.
培养的肿瘤来源的促乳腺细胞（GH3和GC细胞）上促甲状腺激素释放激素（TRH）的质膜受体数量可被雌激素增加，但它们对TRH的亲和力不受影响。对于GH3细胞，暴露于10 nM 17β-雌二醇48小时后，受体水平从54,000个/细胞增加到90,000个/细胞；而对于GC细胞，28小时后受体数量从29,000个增加到46,000个。培养基中催乳素（PRL）的积累也被17β-雌二醇增加。17β-雌二醇和己烯雌酚在增加TRH受体水平方面同样有效，而雌酮的效力仅为其1/10。在GH3和GC细胞中，己烯雌酚与细胞质雌激素受体的结合亲和力比17β-雌二醇高约2.5倍，而对雌酮的亲和力仅为17β-雌二醇的1/12至1/20。他莫昔芬是一种抗雌激素化合物，可抑制0.3 nM 17β-雌二醇诱导的TRH受体数量增加，并且能够与雌激素受体结合。雌激素对促乳腺细胞上TRH受体水平的调节可能是通过细胞质雌激素受体介导的，这可能是调节TRH作用的重要机制。
