Sexual maturation in Growth hormone receptor deficiency chicken.

生长激素(GH)在控制细胞增殖发育、营养代谢、蛋白质合成和繁殖以及正常生长等方面发挥着多种作用。GH作用是在与定位于靶组织的GH受体(GHR)结合后发挥的。缺乏功能性生长激素受体的性连锁矮小鸡是研究生长激素作用的良好实验模型。本研究探讨了GHR缺乏对鸡性成熟的影响。雄性在5-12周龄睾丸有GHR基因的表达。睾丸GHR基因在12周龄前有较高的表达，而在16周龄和成熟雄鼠中未检测到。SLD雏鸡雄性生精小管成熟延迟。目前的研究结果表明，生长激素直接或间接对性成熟有影响。GH与GHR mRNA表达和睾丸小管面积呈负相关，提示GH对精子发生前的睾丸发育有较强的影响。

Growth hormone (GH) plays a various role in controlling cell proliferation and development, nutrient metabolism, protein synthesis and reproduction as well as normal growth. GH actions are exerted after binding to GH receptor (GHR) localized in target tissues. Sex-linked dwarf (SLD) chicken lacking functional GHR is good experimental model for study of GH actions. We investigated effect of GHR deficiency on sexual maturation in chicken. Testicular GHR mRNA was expressed at 5-12 weeks old in male. Testicular GHR mRNA expression was high until 12 weeks old, but which was not detected in 16-weeks old and matured males. Maturation of seminiferous tubule in male was delayed in SLD chicken. Present results suggested that GH was directly or indirectly affected to sexual maturation. Especially, negative correlation with GHR mRNA expression and area of testicular tuble was suggested that GH strongly effect on testicular development, before spermatogenesis.