Nazian S J, Mahesh V B
Arch Androl. 1980 Jun;4(4):283-303. doi: 10.3109/01485018008986974.
Puberty in the male rat is a complex process that involves maturational changes in the hypothalamus, pituitary, testes, and secondary sexual organs and in their interrelationships. During the course of sexual maturation the negative feedback control systems for the gonadotropins become less responsive to testosterone while the testes become more responsive to LH. In the immature rat testosterone can potentiate the effect of LH--RH on pituitary LH release; this response is lost with sexual maturation. LH--RH sensitizes the mature male pituitary glands for subsequent LH--RH administration; this self-priming effect is not present in the immature rat. The responsiveness of the secondary organs to testosterone is also altered with age, as is the relative proportion of testosterone and androstendione secreted by the testes. Experiments designed to prevent or mimic the transition in testicular steroid secretion suggest that it may be a critical component of sexual maturation in the male rat. An elevation in androstendione appears to be capable of delaying the maturation of the LH negative feedback system, the prostate gland, and the LH--RH self-priming effect.
雄性大鼠的青春期是一个复杂的过程，涉及下丘脑、垂体、睾丸和次级性器官及其相互关系的成熟变化。在性成熟过程中，促性腺激素的负反馈控制系统对睾酮的反应性降低，而睾丸对促黄体生成素（LH）的反应性增强。在未成熟大鼠中，睾酮可增强促性腺激素释放激素（LH-RH）对垂体LH释放的作用；随着性成熟，这种反应消失。LH-RH使成熟雄性垂体对随后给予的LH-RH敏感；这种自我启动效应在未成熟大鼠中不存在。次级器官对睾酮的反应性也随年龄而改变，睾丸分泌的睾酮和雄烯二酮的相对比例也是如此。旨在预防或模拟睾丸类固醇分泌转变的实验表明，这可能是雄性大鼠性成熟的一个关键组成部分。雄烯二酮的升高似乎能够延迟LH负反馈系统、前列腺和LH-RH自我启动效应的成熟。
