人精子甘露糖受体的胶体金标记电镜观察

Colloidal Gold Labelling and Locallization for Mannoseligand Receptor of Human Sper matozoa with Electron Microscopy

本文首次报道人精子甘露糖受体（ＭＲ）的电镜标记技术和初步观察。采用甘露糖化牛血清白蛋白（ＤＭＡ，Ｓｉｇｍａ，Ａ８３０３）结合１０ｎｍ胶体金制备探针，标记获能前后精子和甲醇处理或Ａ２３１８７诱导顶体反应（ＡＲ）的精子。结果表明，甲醇处理后ＭＲ表达于顶体区质膜表面，活精子在ＡＲ过程中以不同方式表达ＭＲ活性；ＭＲ定位于：１．ＡＲ早期的精子顶体区质膜表面；２．ＡＲ期间精子的顶体小泡表面、顶体内膜及顶体基质；３．ＡＲ后精子的赤道带顶体内膜和顶体后区质膜；４．ＡＲ后精子的顶体后区质膜。作者认为ＭＲ原来存在于顶体内，大部分可能是膜结合蛋白。在精子发生ＡＲ的过程中ＭＲ才得以暴露并于ＡＲ后逐渐转移至赤道带和顶体后区，可能在精－卵膜融合中发挥介导作用。

At present,we first report the localization of mannose receptors(MR) of human sperm on the electron microscopic level.A novel 10nm gold probe for the detection of MR was made with D Mannosylated BSA(DMA,Sigma,A8303)as DMA G 10 .Human spermatozoa before or after capacitation in BWW or treated with methanol or acrosome reaction(AR) induced with A23187 were respectively labeled with DMA G 10 .MR distributed on the surface of plasma membrane(PM) over acrosome cap after methanol treatment and expressed with different patterns during the period of AR of motile sperm.MR localized on:1.the surface of PM of sperm at the earlier stage of AR;2.the surface of membrane vesicles,inner acrosomal membrane(IAM)or rarely acrosomal matrix of acrosome reacting spermatozoa;3.IAM of equatorial segment(ES) and PM of post acrosome area(PA)after AR;4.PM of post acrosome area only after AR.The conclusion may be that MR might be a kind of molecular primarily stored inside acrosome and most of them associated with acrosomal membrane.They exposes when AR occurs and migrates to equatorial segment and post acrosome area after AR,which might play an important role in mediate the sperm oocyte fusion. 