Kon Hiroe, Takei Gen L, Fujinoki Masakatsu, Shinoda Motoo
Laboratory Animal Research Center, Dokkyo Medical University, Tochigi 321-0293, Japan.
J Reprod Dev. 2014;60(3):202-9. doi: 10.1262/jrd.2013-076. Epub 2014 Mar 10.
It has been recently shown that mammalian spermatozoa were hyperactivated by steroids, amines and amino acids. In the present study, we investigated whether hyperactivation of hamster sperm is regulated by progesterone (P) and γ-aminobutyric acid (GABA). Although sperm hyperactivation was enhanced by P, GABA significantly suppressed P-enhanced hyperactivation in a dose-dependent manner. Suppression of P-enhanced hyperactivation by GABA was significantly inhibited by an antagonist of the GABAA receptor (bicuculline). Moreover, P bound to the sperm head, and this binding was decreased by GABA. Because the concentrations of GABA and P change in association with the estrous cycle, these results suggest that GABA and P competitively regulate the enhancement of hyperactivation through the GABAA receptor.
最近研究表明，哺乳动物精子会被类固醇、胺类和氨基酸激活。在本研究中，我们调查了仓鼠精子的超激活是否受孕酮（P）和γ-氨基丁酸（GABA）调节。尽管P增强了精子超激活，但GABA以剂量依赖的方式显著抑制了P增强的超激活。GABAA受体拮抗剂（荷包牡丹碱）显著抑制了GABA对P增强的超激活的抑制作用。此外，P与精子头部结合，而GABA会减少这种结合。由于GABA和P的浓度会随着发情周期而变化，这些结果表明，GABA和P通过GABAA受体竞争性调节超激活的增强。
