Herndon J G, Bein M L, Nordmeyer D L, Turner J J
Yerkes Regional Primate Research Center, Emory University, Atlanta, Georgia 30322, USA.
Horm Behav. 1996 Sep;30(3):266-71. doi: 10.1006/hbeh.1996.0032.
Some studies report seasonal patterns of testicular function in male rhesus monkeys even when they are housed away from females, while others suggest that exposure to sexually active females is essential for male seasonality. We conducted the present experiment (1) to test claims that seasonal testicular activation occurs in the absence of females and (2) to determine whether regular exposure to and copulation with females enhances, or is without effect upon, seasonal increases in testicular function. We studied two groups of male monkeys housed in a colony room containing no females. Males in the Female Exposure group (n = 7) were paired twice weekly with estradiol-implanted females and copulated vigorously. Males in the second group (n = 7) were placed in the same test chamber (at least 16 h after it had been scrubbed with disinfectant) but were never exposed to females. Serum testosterone levels and testis volume were monitored for both groups. Each group displayed a seasonal pattern of testosterone and of testis volume comparable in timing and magnitude to seasonal increases previously reported in group-housed males, but the two groups did not differ from each other. Our findings confirm that seasonal changes in testosterone and testis size occur in the absence of sexual interaction and demonstrate that moderate levels of sexual activity do not enhance this response.
一些研究报告称，即使雄性恒河猴被饲养在远离雌性的环境中，其睾丸功能仍呈现季节性变化模式，而另一些研究则表明，接触性活跃的雌性对雄性的季节性变化至关重要。我们进行了本实验，一是为了验证在没有雌性的情况下睾丸是否会出现季节性激活的说法，二是为了确定定期与雌性接触并交配是否会增强或不影响睾丸功能的季节性增加。我们研究了两组饲养在没有雌性的群体饲养室中的雄性猴子。雌性接触组的雄性猴子（n = 7）每周与植入雌二醇的雌性猴子配对两次，并进行激烈交配。第二组的雄性猴子（n = 7）被放置在同一个测试室（在该测试室用消毒剂擦洗至少16小时后），但从未接触过雌性猴子。对两组猴子的血清睾酮水平和睾丸体积进行了监测。每组猴子的睾酮水平和睾丸体积都呈现出季节性变化模式，在时间和幅度上与之前报道的群居雄性猴子的季节性增加相当，但两组之间没有差异。我们的研究结果证实，在没有性互动的情况下，睾酮和睾丸大小会发生季节性变化，并表明适度的性活动并不会增强这种反应。
