人精子雌激素结合位点的研究

STUDY OF ESTROGEN BINDING SITE ON HUMAN EJACULATED SPERMATOZOA

用电镜放射自显影技术对人射出精子17β-雌二醇结合位点进行定位研究,结果表明此位点位于精子细胞膜上,分布在顶体区、赤道区、顶体后区、尾部中段等不同部位。用放射配体受体法对正常生育男性射出精子雌激素结合位点进行定量测定,其最佳实验条件为:(1)精子与氚标雌二醇在0℃～4℃保温18～20小时,细胞与激素才能达到充分的结合。(2)精子悬液浓度为80-130×10_6/ml时,细胞与加入的~3H-E_2比例适当,可有良好的结合。(3)精子活动率低时能与~3H-E_2发生特异性结合的精子少,本实验所测的精子活动率在40％以上。实验结果表明人精子雌激索结合位点的含量为0.75±0.38×10^(-3)pmole/10~7精子,但此位点尚不能认为是雌激素受体。

The specific estrogen binding site for 17β-estradiol has been investigated on human spermatozoa by electron microscopic autoradiography.The results showed that the binding sites were distributed over the surface of human spermatozoa: acrosomal cap, equatorial segment, postacrosomal cap, and the midpiece and principal piece of the tail. 17β-estradiol binding sites on ejaculated spermatozoa of fertile males were also quantitatively determinded by Radio-Ligand Receptor Binding Assay,The studies on the in vitro binding of (~3H)estradiol to spermatozoa, under the optimal experimental conditions, showed that:(1) Aliquots should be incubated at 0℃-4℃ for 18-20hours.(2) The binding was the best when the cell concentration was 80-130×10~6 sperm/ ml.(3) The ratio of the motile spermatozoa may affect the binding of (~3H) estradiol to sperm .Only those samples with motility greater than 40% were used. The binding capacity of sperm was 0.75±0.38×10^(-3) pmole/10~7 sperm. The binding site of 17β-estradiol human sperm might not be a 17β-estradiol receptor.