Giebel J, Löster K, Rune G M
Department of Anatomy, Ernst Moritz Arndt University Greifswald, Germany.
Int J Androl. 1997 Feb;20(1):3-9. doi: 10.1046/j.1365-2605.1997.d01-105.x.
Very late activation (VLA, beta 1; alpha 1; alpha 5, alpha 9) integrins were studied by immunoblotting and immunohistochemistry in the testes of sexually mature rats. All integrin subunits were present in membrane fractions of homogenized testes. Immunohistochemistry revealed that the anti beta 1 antibody recognized peritubular cells and the basement membrane of blood vessels. Immunoreactivity was also demonstrated in the lamina propria, basement membrane, and the basal cytoplasm of Sertoli cells. In elongating spermatids, beta 1 integrin was localized to the acrosome. The alpha 1 subunit was expressed in peritubular cells and in the lamina propria. In the adluminal compartment, round spermatids were stained diffusely for the alpha 1 subunit. Immunoreactivity for alpha 1 integrin was found additionally in the acrosomes of elongating spermatids shortly before their release into the seminiferous tubule lumen. The alpha 5 subunit was expressed in the acrosomes of elongating spermatids as well as in their distal cytoplasm during stages III-VI; the cytoplasmic lobes of elongate spermatids and/or residual bodies also appeared to be immunostained in seminiferous tubules at stages VII-VIII. The alpha 9 subunit was immunolocalized only in the basement membrane and in peritubular cells. These data suggest that integrins are involved in spermatogenesis, in particular in the process of spermatid maturation.
通过免疫印迹法和免疫组织化学法，对性成熟大鼠睾丸中的极晚期激活（VLA，β1；α1；α5，α9）整合素进行了研究。所有整合素亚基均存在于匀浆睾丸的膜组分中。免疫组织化学显示，抗β1抗体识别睾丸白膜细胞和血管基底膜。在固有层、基底膜和支持细胞的基底细胞质中也证实有免疫反应性。在伸长的精子细胞中，β1整合素定位于顶体。α1亚基在睾丸白膜细胞和固有层中表达。在近腔室中，圆形精子细胞的α1亚基呈弥漫性染色。在伸长的精子细胞释放到生精小管管腔前不久，其顶体中额外发现了α1整合素的免疫反应性。在III - VI期，α5亚基在伸长的精子细胞的顶体及其远端细胞质中表达；在VII - VIII期的生精小管中，伸长精子细胞的细胞质叶和/或残余小体似乎也有免疫染色。α9亚基仅免疫定位于基底膜和睾丸白膜细胞中。这些数据表明，整合素参与精子发生过程，特别是在精子细胞成熟过程中。
