Different transcriptional levels of GABA_A receptor subunits in mouse cumulus cells around oocytes at different mature stage

Abstract

γ-Aminobutyric acid (GABA) is a principal inhibitory neurotransmitter in the central nervous system (CNS) of vertebrates. However, GABA and its receptor are found not only in peripheral neuronal tissue but also in many peripheral nonneuronal tissues, and thought to have multiple physiological functions. The bidirectional communication between oocytes and cumulus cells (CCs) plays a significant role in oocyte maturation and metabolism. In our previously study, the expression level of α5 subunit in CCs isolated from oocytes of patients with polycystic ovary syndrome had been found to be associated with oocyte nuclear maturity. In this study, we investigated the transcriptional levels of GABA_A receptor subunits in germinal vesicle (GV) and metaphase II (MII) mouse CCs, and explored the role of GABA-A receptor subunits during ovarian follicular development and oocyte maturation. We found that GABA_A receptor subunits exhibited differential transcriptional levels in CCs at different oocyte nuclear maturity stages. It suggested an involvement of GABA-A receptor subunits related to oocyte maturation and certain functions.

Chinese abstract

γ-氨基丁酸(GABA) 是脊椎动物中枢神经系统(CNS)中的一种主要抑制性神经递质。然而, GABA 和其受体不仅见于周围神经组织, 还见于许多周围非神经组织, 认为其具有多种生理功能。卵母细胞和卵丘细胞(CCs)之间的双向通信在卵母细胞的成熟和代谢过程中起着重要作用。在我们之前的研究中, 发现多囊卵巢综合征患者与卵母细胞隔离的卵丘细胞中α5亚基的表达水平与卵母细胞核的成熟有关。在本研究中, 我们研究小鼠卵丘细胞在生发泡(GV)和分裂II期(MII)GABA_A受体亚基的转录水平, 探讨GABA-A受体亚基在卵巢卵泡发育和卵母细胞成熟中的作用。我们发现卵丘细胞中的GABA_A受体亚基在不同的卵母细胞核成熟阶段表现出不同的转录水平。提示GABA-A受体亚基参与卵母细胞成熟并具有一定的功能。

Keywords:

• Cumulus cells
• GABA
• GABA receptor
• mouse
• oocyte maturation

Acknowledgements

The authors would like to gratefully thank Luo Qianqian and Zhao Wei for advice on WB and immunohistofluorescence technology.

Declaration of interest

The authors declared no conflicts of interest. This study was supported by the National Science Foundation of China [grant number 81170622].