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本文综述了哺乳动物精子获能和顶体反应过程中精子膜主要相关配体和受体。白蛋白从精子细胞膜脂质中除去胆固醇使得膜脂质结构和流动性发生了变化 ,从而使镶嵌在脂质中功能蛋白质的拓朴结构、膜通透性、膜电位发生了改变。孕酮与相应受体的结合通过开启配体依赖性钙离子通道 ,使精子细胞内钙离子浓度升高 ,在其它因素的综合作用下 ,使精子获能。ZP(卵子透明带 )通过与精子膜相应受体结合使得电压依赖性钙离子通道开放促进细胞外钙离子内流 ,并通过G蛋白介导 ,活化磷脂酶分解肌醇二磷酸产生IP3(肌醇三磷酸 ) ,IP3作用于顶体门控钙离子通道引起精子细胞内钙离子动员 ,使细胞内钙离子浓度急剧升高。位于鞭毛的环核甘酸门控钙离子通道在环核甘酸的作用下调节着鞭毛运动。环境获能相关因子与精子膜相关结构的作用使细胞内第二信使增加 ,PKA(蛋白激酶A)、PKC(蛋白激酶C)、酪氨酸激酶等激酶系统活化通过酶促链锁反应使顶体酶系激活 ,引起了顶体反应和精卵融合。蛋白质酪氨酸磷酸化是孕酮、ZP3等生理因子和配体结合后引发的蛋白质主要活化形式。自由基在精子获能和顶体反应过程中起着重要的分子信号作用
This review summarizes the major ligands and receptors involved in sperm membrane during mammalian sperm capacitation and acrosome reaction. Albumin removes cholesterol from sperm cell membrane lipids, which changes the membrane lipid structure and fluidity, thus changing the topological structure, membrane permeability and membrane potential of the functional proteins embedded in the lipid. The combination of progesterone and its corresponding receptor enables the sperm to be capacitated by opening the ligand-dependent calcium channel and increasing the intracellular calcium concentration in the sperm cell under the combined action of other factors. ZP (egg zona pellucida) promotes the influx of extracellular calcium through the opening of voltage-dependent calcium channels by binding to the corresponding receptors on the sperm membrane, and activates phospholipases to decompose inositol diphosphate to produce IP3 (inositol Triphosphate), IP3 role in the acrosome-dependent calcium channel caused by sperm intracellular calcium mobilization, so that a sharp increase in intracellular calcium concentration. Cyclic nucleoside-gated calcium channels located in the flagella modulate flagellar motility under the action of cyclic nucleotides. Environmental capacitation-related factors and sperm membrane-related role in the structure of the second messenger cell increased, PKA (protein kinase A), PKC (protein kinase C), tyrosine kinase and other kinase system activation by enzymatic chain reaction to the top Systemic enzyme activation, causing the acrosome reaction and sperm-egg fusion. Protein tyrosine phosphorylation is a pro-form of pro-progesterone, a physiological activator of ZP3, and a protein that is triggered by ligand binding. Free radicals play an important role as molecular signals in sperm capacitation and acrosome reaction