精子膜表面配体依赖性离子通道与精子顶体反应

Function of Sperm Membrane Ligand-gated Ion Channels in Sperm Acrosome Reaction

配体依赖性离子通道是一类由神经递质调控的跨膜离子通道。研究发现它们在精子的顶体反应中起了重要作用,顶体反应是精子完成受精的一个关键步骤。至今已发现3种配体依赖性离子通道受体存在于精子头部的质膜上,它们是乙酰胆碱受体、甘氨酸受体和GABAa受体。尽管乙酰胆碱受体和甘氨酸受体已被清楚的证明参与了ZP3诱导的顶体反应,GABAa受体的功能则相对复杂,需进一步研究。这类受体在精子膜电压变化中起的作用和由此导致的膜电位改变对于精子顶体反应的重要性,为精子顶体反应提供了一个可能的信号传递途径。

Ligand-gated ion channels are membrane-spanning ion channels gated by neurotransmitters. Researches found out they play an important role in sperm acrosome reaction （AR）, a fundamental step needed for mammalian fertilization. So far, three kinds of ligand-gated ion channels were detected in sperm head membrane, they are ACh receptor, glycine receptor, and GABAa receptor. Though ACh receptor and glycine receptor are clearly involved in Zona pellucida 3 （ZP3）-induced AR, the function of GABAa receptor are much more complicate. This review means to elucidate the different mechanisms of those receptors in changing of sperm membrane potential, and provide a partial view of sperm AR signal transduction passway.