重组于脂双层的人精子质膜Ca2+通道的膜片箝研究

跨膜离子流动在启动配子间的相互作用,如顶体反应过程中有重要作用。．但由于精子太小,无用论细胞内记录或膜片箝技术都难以对哺乳动物精子膜的离子通病进行研究。本工作将通道蛋白重组于脂双层,在电压箝位下记录了人精子膜的Ｃａ＾２＋通道电流。由１２个健康人的精子分离的膜蛋白通过融合重组于脂双层后,在ＣａＣｌ２溶液中（ｃｉｓ５０／／ｔｒａｎｓ １０ｍｍｏｌ／Ｌ）记录到两类单通道活动,它们的平衡电位都接近Ｃａ＾２

A patch clamp study on reconstituted calcium permeable channels of human sperm plasma membranes

Ionic flux is thougb to be Anportan in the inihating pe of pe interachon such asacrosome reaction. Howewr, modem electrophyological metods , intracellular recording and Patoh-clamping,are ffeult to approach the ion channch in mammal sperm membrane of an intact sperm due to its small size.In this work, by reconstituting the channel win into lipul bilayer, Ca2 channels in human speozoawere inVedgatal with voltag clamp technique. Membrane protains isolatal bo human sperm of 12 healthdonors were incoporated into lipid bilayer via fusion. In a cis 50//trans 10 mmol/L CaCl2 solution system,two pe of chaxmel eVents with similar reversal potential near the value of a peho Ca eleced, andSendtive to nifedipine and verapamil, were for. ber wht conductance was 40 and 25 pS mendvely.Pementag of channel pe the was at dependent to holding potential for tha foarer. Howevr, for thecbo of 25 gh, the pemp increased when the hokhag potential was changed from - 20 to 100 mV.Ca2 -permeable channels were the detectal bo the spermatco Saznpe of two infertile dsnors. Abnormal open the of these cbo edcates tha bo are some defects in tha conformaon of the channe protein of infertile spenn membran.