Puberty is delayed in male growth hormone receptor gene-disrupted mice.
Puberty is delayed in male growth hormone receptor gene-disrupted mice.
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DOI：
10.1002/j.1939-4640.2002.tb02308.x
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发表时间：
2002-09
影响因子：
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通讯作者：
D. E. Keene;M. Suescun;Melissa G Bostwick;V. Chandrashekar;A. Bartke;J. Kopchick
中科院分区：
文献类型：
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作者：
D. E. Keene;M. Suescun;Melissa G Bostwick;V. Chandrashekar;A. Bartke;J. Kopchick
胰岛素样生长因子-I（IGF-I）在青春期和睾丸功能启动中的作用知之甚少。生长激素（GH）受体（R）基因破坏的小鼠或GHR基因“敲除”（GHR-KO）是GH抗性和IGF-I缺陷的。为了评估性成熟的年龄是否受IGF-I缺乏的影响，在25至60日龄的正常和GHR-KO小鼠中测定了性发育的各种参数，包括睾丸和辅助生殖器官重量、龟头包皮分离、生殖细胞发育和睾丸内睾酮水平。此外，在36日龄时，在这些小鼠中评估了睾酮对促黄体激素（LH）治疗的反应。结果表明，龟头包皮分离延迟5天，和精囊（SV）的重量显着增加发生在较晚的GHR-KO小鼠比正常动物（30和35天之间和35和40天之间，分别）。此外，GHR-KO小鼠的睾丸和附睾重量显著降低。睾丸内睾酮水平和睾酮对LH治疗的反应在GHR基因破坏的小鼠中减弱。此外，在GHR-KO小鼠睾丸中，细长的精子细胞比正常小鼠睾丸中出现得晚。这些结果表明，IGF-I分泌的缺乏延迟了雄性GHR-KO小鼠性成熟的正常过程，表明IGF-I在雄性小鼠青春期的启动中起重要作用。
The role of insulin-like growth factor-I (IGF-I) in the initiation of puberty and testicular function is poorly understood. Growth hormone (GH) receptor (R) gene-disrupted mice or GHR gene "knockouts" (GHR-KO) are GH resistant and IGF-I deficient. To assess whether the age of sexual maturation is affected by the absence of IGF-I, various parameters of sexual development including testicular and accessory reproductive organ weights, balanopreputial separation, germ cell development, and intratesticular testosterone levels were determined in normal and GHR-KO mice between the ages of 25 and 60 days. In addition, at 36 days of age, the testosterone response to luteinizing hormone (LH) treatment was assessed in these mice. The results indicate that the balanopreputial separation was delayed 5 days, and a significant increase in the weights of the seminal vesicles (SV) occurred later in GHR-KO mice than in normal animals (between 30 and 35 days and between 35 and 40 days, respectively). Also, the weights of testes and epididymii were significantly reduced in GHR-KO mice. The intratesticular testosterone levels and the testosterone response to LH treatment were attenuated in GHR gene-disrupted mice. Furthermore, elongated spermatids appeared later in the testes of GHR-KO mice than in the testes of normal mice. These results suggest that the absence of IGF-I secretion delays the normal course of sexual maturation in male GHR-KO mice, indicating that IGF-I plays an important role in the initiation of puberty in male mice.