Testicular responsiveness to gonadotropic hormonein vitro and Leydig and Sertoli cell ultrastructure during pubertal development of male African catfish (Clarias gariepinus)
Testicular responsiveness to gonadotropic hormonein vitro and Leydig and Sertoli cell ultrastructure during pubertal development of male African catfish (Clarias gariepinus)
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雄性非洲鲶鱼（Clarias gariepinus）青春期发育过程中睾丸对促性腺激素的体外反应以及间质和支持细胞超微结构
DOI：
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发表时间：
1996
影响因子：
2.9
通讯作者：
H. Goos
中科院分区：
文献类型：
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作者：
R. Schulz;K. Lubberink;M. A. Zandbergen;C. Janssen;J. Peute;H. Goos
研究了雄性非洲鲶鱼青春期发育过程中促性腺激素（GTH）刺激的体外睾丸雄激素分泌以及间质细胞和支持细胞的超微结构。睾丸重量从第9周时的不足1毫克增加到第28周时的近600毫克。未成熟的睾丸（第一阶段：精原细胞）对 GTH 高度敏感，每毫克组织分泌大量雄激素。每毫克组织的分泌量在第二阶段（精原细胞和精母细胞）和第三阶段（精原细胞、精母细胞和精细胞）逐渐下降，但在第四阶段（所有生殖细胞阶段，包括精子）急剧下降。然而，由于睾丸重量增加，每对睾丸的总雄激素输出量在第三阶段略有增加，在第四阶段则大幅增加。随着III期单倍体生殖细胞的出现，对GTH的敏感性降低。 Leydig 细胞而非支持细胞显示出类固醇产生细胞的超微结构特征。间质细胞形态在 I-III 阶段没有变化，而在 IV 阶段，出现了更光滑的内质网。支持细胞的超微结构特征没有明显变化。因此，当睾丸类固醇生成系统高度活跃并对 GTH 敏感时，就会发生精原细胞增殖和精母细胞形成。而单倍体生殖细胞的分化伴随着对 GTH 的反应性降低以及每毫克组织分泌的雄激素量降低数倍。
The gonadotropin (GTH)-stimulated testicular androgen secretionin vitro and the ultrastructure of Leydig and Sertoli cells was studied during the pubertal development in male African catfish. Testicular weight increased from less than 1 mg in the ninth week of age to nearly 600 mg in the 28th week. Immature testes (stage I: spermatogonia) were highly sensitive to GTH and secreted very high amounts of androgens per mg of tissue. The secretion per mg tissue decreased gradually in stages II (spermatogonia and spermatocytes) and III (spermatogonia, spermatocytes, and spermatids), but precipitously in stage IV (all germ cell stages, including spermatozoa). However, due to the testicular weight gain, the total androgen output per pair of testes increased slightly in stage III and strongly in stage IV. The sensitivity to GTH decreased with the appearance of haploid germ cells in stage III. Leydig cells but not Sertoli cells showed the ultrastructural characteristics of steroid producing cells. Leydig cell morphology did not change in stages I–III, while in stage IV, more smooth endoplasmic reticulum was present. The ultrastructural characteristics of Sertoli cells did not change prominently. Thus, spermatogonial multiplication and spermatocyte formation takes place when the testicular steroidogenic system is highly active and responsive to GTH; whereas the differentiation of haploid germ cells is accompanied by a reduced responsiveness to GTH and by the secretion of several-fold lower androgen amounts per mg of tissue.