Department of Zoology, Michigan State University, East Lansing, MI 48824, USA.
Horm Behav. 2010 Apr;57(4-5):488-95. doi: 10.1016/j.yhbeh.2010.02.007. Epub 2010 Feb 19.
In the rat, neonatal administration of testosterone propionate to a castrated male causes masculinization of behavior. However, if an intact male is treated neonatally with testosterone (hyper-androgen condition), male sexual behavior in adulthood is disrupted. There is a possibility that the hyper-androgen treatment is suppressing male sexual behavior by altering the male's partner preference and thereby reducing his motivation to approach the female. If so, this would suggest that exposure to supra-physiological levels of androgen during development may result in the development of male-oriented partner preference in the male. To test this idea, male rats were treated either postnatally or prenatally with testosterone, and partner preference and sexual behavior were examined in adulthood. The principal finding of this study was that increased levels of testosterone during early postnatal life, but not prenatal, decreased male sexual behavior and increased the amount of time a male spent with a stimulus male, without affecting the amount of time spent with a stimulus female during partner preference tests. Thus, the reduction in male sexual behavior produced by early exposure to high levels of testosterone is not likely due to a reduction in the male's motivation to approach a receptive female.
在雄性大鼠中，新生期丙酸睾丸酮的给予会导致行为的雄性化。然而，如果将完整的雄性动物在新生期用睾酮（高雄性激素条件）处理，则成年雄性性行为会受到破坏。有一种可能是，高雄性激素处理通过改变雄性的伴侣偏好从而降低其接近雌性的动机来抑制雄性性行为。如果是这样，这将表明在发育过程中暴露于超生理水平的雄激素可能导致雄性对雄性的伴侣偏好的发展。为了检验这一想法，雄性大鼠在出生后或产前接受睾酮处理，并在成年期检查伴侣偏好和性行为。这项研究的主要发现是，在早期新生期而不是产前增加的睾酮水平会降低雄性的性行为，并增加雄性与刺激雄性花费的时间，而不会影响雄性在伴侣偏好测试中与刺激雌性花费的时间。因此，早期暴露于高水平睾酮导致的雄性性行为减少不太可能是由于雄性接近接受雌性的动机降低所致。
