Influence of estradiol-17β, testosterone, and 11-ketotestosterone on testicular development, serum steroid hormone, and gonadotropin secretion in male red sea bream Pagrus major
Influence of estradiol-17β, testosterone, and 11-ketotestosterone on testicular development, serum steroid hormone, and gonadotropin secretion in male red sea bream Pagrus major
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DOI：
10.1111/j.1444-2906.2006.01225.x
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发表时间：
2006-08
影响因子：
1.9
通讯作者：
S. Yamaguchi;K. Gen;K. Okuzawa;M. Matsuyama;H. Kagawa
中科院分区：
文献类型：
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作者：
S. Yamaguchi;K. Gen;K. Okuzawa;M. Matsuyama;H. Kagawa
为探讨雌、雄激素对雄性硬骨鱼生殖活动的影响，在未成熟期和生精早期将含有雌二醇（E2）、睾酮（T）和11-酮睾酮（11-KT）的硅胶囊植入雄性真鲷体内。无论是E2或T植入后一个月，性腺指数下降，按照睾丸退化在这两个阶段。E2的植入降低了循环11-KT水平，但不影响促性腺激素（GTH）亚基、促卵泡激素-β（FSHβ）、促黄体激素-β（LHβ）、α糖蛋白亚基（αGSU）基因表达和血清LH水平。T可降低生精早期血清11-KT和LH水平及FSHβ和LHβ mRNA水平，但对未成熟期无影响。这些结果表明，E2可能通过抑制FSH和LH的分泌而直接抑制睾丸发育，从而抑制早期生精阶段的睾丸发育。11-KT处理对两个阶段的睾丸均无影响，但11-KT可增加未成熟睾丸LHβ和αGSU mRNA的表达，降低生精早期FSHβ mRNA的表达。这些结果表明，11-KT可能对GTH亚基基因在生殖各个阶段的表达有不同的影响。
In order to investigate the influence of estrogen and androgen on reproductive activities of male teleosts, male red sea bream were implanted with silicone capsules containing estradiol-17β (E2), testosterone (T) or 11-ketotestosterone (11-KT) in immature and early spermatogenic stage. One month after implantation of either E2 or T, the gonadosomatic index decreased in accordance with testicular regression in both stages. Implantation of E2 decreased circulating 11-KT levels but did not affect gonadotropin (GTH) subunits, follicle stimulating hormone-β (FSHβ), luteinizing hormone-β (LHβ), α glycoprotein subunit (αGSU) gene expression, and serum LH levels in both stages. Alternatively, T decreased serum 11-KT and LH levels, and FSHβ and LHβ mRNA levels in the early spermatogenic stage but not in the immature stage. These results suggest E2 may directly inhibit testicular development through the suppression of FSH and LH secretion, resulting to inhibition of testicular development in the early spermatogenic stage. Treatment with 11-KT did not affect the testis in either stage, whereas 11-KT increased LHβ and αGSU mRNA levels in immature, and decreased FSHβ mRNA levels in the early spermatogenic stage. These results suggest that 11-KT may have different effects on GTH subunit gene expression in each reproductive stage.