Fru K N, Cherian-Shaw M, Puttabyatappa M, VandeVoort C A, Chaffin C L
Department of Physiology, Medical College of Georgia, Augusta, GA, USA.
Hum Reprod. 2007 May;22(5):1247-52. doi: 10.1093/humrep/del519. Epub 2007 Feb 9.
This study seeks to clarify cell cycle dynamics of granulosa cells following hCG and elucidate the expression of epidermal growth factor (EGF)-like ligands during luteinization.
Granulosa cells were obtained from rhesus macaques undergoing controlled ovarian stimulation protocols before or after an ovulatory hCG bolus. Cell cycle characteristics were determined by flow cytometry and levels of EGF receptor (EGFR), amphiregulin (AREG), epiregulin (EREG) and betacellulin (BTC) mRNAs were measured by real-time RT-PCR.
The proportion of cells in S-phase was 7.5% prior to hCG and did not decline until 24 h after hCG (3.1%). EGFR protein and BTC mRNA did not change following hCG, whereas AREG and EREG mRNA increased starting at 3 and 12 h post-hCG, respectively, and remained elevated thereafter.
Cell cycle transit of macaque granulosa cells does not change until 24 h after an ovulatory stimulus, whereas the EGF-like ligands EREG and AREG are increased rapidly. This suggests that luteinizing granulosa cells are refractory to mitogenic stimulation by EGFR ligands.
本研究旨在阐明人绒毛膜促性腺激素（hCG）作用后颗粒细胞的细胞周期动态变化，并阐明黄体化过程中表皮生长因子（EGF）样配体的表达情况。
从接受控制性卵巢刺激方案的恒河猴中获取颗粒细胞，分别在排卵性hCG推注前或后采集。通过流式细胞术确定细胞周期特征，并通过实时逆转录聚合酶链反应（RT-PCR）测量表皮生长因子受体（EGFR）、双调蛋白（AREG）、表皮调节素（EREG）和β细胞素（BTC）的信使核糖核酸（mRNA）水平。
hCG注射前处于S期的细胞比例为7.5%，直到hCG注射后24小时才下降（3.1%）。hCG注射后，EGFR蛋白和BTC mRNA没有变化，而AREG和EREG mRNA分别在hCG注射后3小时和12小时开始增加，并在随后保持升高。
排卵刺激后24小时内，猕猴颗粒细胞的细胞周期进程没有变化，而EGF样配体EREG和AREG迅速增加。这表明黄体化的颗粒细胞对EGFR配体的促有丝分裂刺激具有抗性。
