摘要
下丘脑-垂体-睾丸轴系对男性生殖功能起着关键性作用,精子发生是这个轴系精密调节的结果。下丘脑促性腺激素释放激素(GnRH)脉冲式释放控制了卵泡刺激素(FSH)和黄体生成素(LH)的波动性分泌,GnRH脉冲频率的变化调节垂体促性腺细胞分泌两种不同的激素,是一种独具一格的机制。促性腺激素抑制激素(GnIH)于2000年首次从鹌鹑垂体鉴定出来。GnIH的发现使我们更深入地了解下丘脑激素对垂体促性腺细胞的调节。哺乳动物的GnIH神经元定位于下丘脑背内侧核,轴突延伸至正中隆突。GnIH通过其受体GPR147抑制垂体促性腺细胞的功能。成年男子的精子发生需要FSH和睾酮的共同作用,任何二者之一缺失会损害Sertoli细胞的分化和功能以及生精细胞在精子发生过程的发育。睾酮至少从4个方面促进精子发生:(1)紧密连接(tight junction)的形成和功能;(2)附睾的发育和功能;(3)生精细胞的发育;(4)精子释放。在体研究提示,雌激素亦对精子发生起重要作用,雌二醇调节小鼠精原细胞系和精母细胞系调亡和抗调亡之间的平衡。
The hypothalamic-pituitary-testis axis plays a critical role in male reproduction.Spermatogenesis relies on precise hormonal regulation of this axis.Oscillatory FSH and LH secretion are under control of pulsatile release of GnRH.Variation in GnRH pulse frequency is associated divergent FSH and LH secretion,providing a mechanism by which a single hypothalamic hormone can induce differential change in two distinct hormones released from the same pituitary gonadotropes.Gonadotropininhibiting hormone（GnIH）was first identified in pituitary gland of quail in 2000.The identification of GnIH is a greater insight into the regulation of hypothalamic hormones on pituitary gonadotropes.GnIH neurons are located in the hypothalamic medial dorsal nucleus area in mammals,and project to the median eminence to play the inhibitory roles on anterior pituitary gland via its receptor GPR147 expressed in gonadotropes.Spermatogenesis in adult male depends on the action of FSH and testosterone.Ablation of either hormone has deleterious effects on Sertoli cell proliferation and functioning,and the development of germ cells through spermatogenesis.The promoting effects of testosterone on spermatogenesis include：（1）the formation and functioning of tight junction;（2）the development and functioning of epididymis;（3）the development of sperm cells;（4）spermiation.Studies in vivo confirm that estrogens play important roles in the regulation of spermatogenesis.Estradiol mediates the balance between anti-apoptosis and apoptosis in mouse spermatogonial cell line and spermatocyte-derived cell line.
出处
《生殖医学杂志》
CAS
2014年第9期697-702,共6页
Journal of Reproductive Medicine
