Wang Cheng, Prossnitz Eric R, Roy Shyamal K
Department of Obstetrics and Gynecology, University of Nebraska Medical Center, 984515 Nebraska Medical Center, Omaha, NE 68198-4515, USA.
Endocrinology. 2007 Oct;148(10):4853-64. doi: 10.1210/en.2007-0727. Epub 2007 Jul 19.
The nongenomic actions of estradiol-17beta are mediated by transmembrane estrogen receptors. Recently, G protein-coupled receptor 30 (GPR30) has been suggested to be a transmembrane estrogen receptor that can mediate rapid and transcription-independent estradiol-17beta signaling in different cell types. However, the expression, regulation, or biological relevance of GPR30 in the ovary remains unknown. We examined the expression and hormonal regulation of GPR30 mRNA and protein in hamster ovarian cells during the estrous cycle and after hypophysectomy and hormone replacement. GPR30 protein expression was high in the theca, appreciable in the granulosa, but low in luteal cells. GPR30 protein levels in granulosa and theca cells increased steadily with the development of preantral and antral follicles, respectively. GPR30 mRNA and protein levels increased significantly on diestrous (d 3 of the estrous cycle), but decreased on d 4 at 1600 h after the LH surge. GPR30 mRNA levels increased significantly after hypophysectomy. Although steroid treatment failed to alter ovarian GPR30 mRNA levels, either FSH or LH effectively reduced the levels. Interestingly, the decrease in GPR30 mRNA corresponded to a marked increase in the receptor protein levels. FSH treatment, either alone or together with LH, resulted in a marked increase in GPR30 immunostaining in granulosa cells. LH alone significantly increased immunostaining in theca cells. These results suggest that GPR30 is expressed in the membrane of hamster granulosa and theca cells, and the expression is regulated by gonadotropins. The unique pattern of GPR30 expression suggests that gonadotropin-regulated follicular cell functions may involve GPR30 activity.
17β-雌二醇的非基因组作用由跨膜雌激素受体介导。最近，G蛋白偶联受体30（GPR30）被认为是一种跨膜雌激素受体，它可以在不同细胞类型中介导快速且不依赖转录的17β-雌二醇信号传导。然而，GPR30在卵巢中的表达、调节或生物学相关性仍不清楚。我们研究了动情周期期间、垂体切除术后以及激素替代后仓鼠卵巢细胞中GPR30 mRNA和蛋白的表达及激素调节情况。GPR30蛋白表达在卵泡膜细胞中较高，在颗粒细胞中可观，但在黄体细胞中较低。颗粒细胞和卵泡膜细胞中的GPR30蛋白水平分别随着窦前卵泡和窦卵泡的发育而稳步增加。GPR30 mRNA和蛋白水平在动情后期（动情周期的第3天）显著升高，但在促黄体生成素高峰后第4天16:00时下降。垂体切除术后GPR30 mRNA水平显著升高。虽然类固醇处理未能改变卵巢GPR30 mRNA水平，但促卵泡生成素或促黄体生成素均有效降低了其水平。有趣的是，GPR30 mRNA的降低对应于受体蛋白水平的显著增加。单独使用促卵泡生成素或与促黄体生成素联合使用，均可导致颗粒细胞中GPR30免疫染色显著增加。单独使用促黄体生成素可显著增加卵泡膜细胞中的免疫染色。这些结果表明，GPR30在仓鼠颗粒细胞和卵泡膜细胞的膜中表达，且其表达受促性腺激素调节。GPR30表达的独特模式表明，促性腺激素调节的卵泡细胞功能可能涉及GPR30活性。
