人类精子细胞膜中的肝素结合位点。

Heparin binding sites in the human spermatozoa membrane.

作者信息

Delgado N M, Reyes R, Huacuja L, Merchant H, Rosado A

出版信息

Arch Androl. 1982 Mar;8(2):87-95. doi: 10.3109/01485018208987024.

DOI:10.3109/01485018208987024

Abstract

The existence in the human spermatozoa membrane of receptorlike functional group for heparin was studied. Incubation of whole spermatozoa with tritiated heparin induced the specific binding of 745 +/- 112 pmol of heparin per 5 x 10(7) sperm cells with an intrinsic association constant KD = 3.6 x 10(-6) M. The specificity of binding was shown by the lack of competence in the binding process of some other glycosaminoglycans used at concentrations 20 x higher than heparin. However, dextran sulfate was a very efficient competitive agent. Autoradiography experiments showed that labeling was almost completely restricted to sperm cells in the process of nuclear decondensation. This technique showed the presence of a high amount of radioactive heparin in the isolated sperm membranes even after several washings. Heparin may participate both in the final part of the capacitation process (acrosome reaction) and in the decondensation of sperm nuclei.

摘要

研究了人类精子细胞膜上类肝素受体样功能基团的存在情况。用氚标记的肝素孵育完整精子，每5×10⁷个精子细胞可诱导745±112 pmol肝素的特异性结合，内在结合常数KD = 3.6×10⁻⁶ M。一些其他糖胺聚糖在浓度比肝素高20倍时参与结合过程的能力缺失，表明了结合的特异性。然而，硫酸葡聚糖是一种非常有效的竞争剂。放射自显影实验表明，在核解聚过程中，标记几乎完全局限于精子细胞。该技术表明，即使经过多次洗涤，在分离的精子膜中仍存在大量放射性肝素。肝素可能参与获能过程的最后阶段（顶体反应）以及精子细胞核的解聚。