Department of Psychology, University of Virginia, Charlottesville, Virginia 22903, USA.
J Neuroendocrinol. 1991 Aug 1;3(4):441-8. doi: 10.1111/j.1365-2826.1991.tb00301.x.
Abstract The experiments reported on here were conducted to test the hypothesis that sexual behaviour in the female musk shrew (Suncus murinus) is regulated by the neural aromatization of testosterone to oestradiol. In the first experiment ovariectomized animals received subcutaneous hormone implants containing either an aromatizable androgen (testosterone or androstenedione), a non-aromatizable androgen (dihydrotestosterone or methyltrienolone), or cholesterol. Only females that received an aromatizable androgen exhibited significant amounts of sexual behaviour as compared with controls (cholesterol). To examine the role of the oestrogen receptor, the anti-oestrogen, tamoxifen (200 or 400 mug daily) was given to ovary intact or ovariectomized females treated with testosterone. Tamoxifen treatment had significant negative effects both on female sexual behaviour and on the weights of several peripheral tissues as compared with control treatments. A similar set of experiments was conducted to examine the effect of an anti-androgen on female sexual behaviour. The androgen receptor blocker, flutamide, had no effect on sexual behaviour or weights of peripheral tissues. To determine whether flutamide can act as an anti-androgen in this species two final experiments were conducted in male musk shrews. Flutamide treatment in males did affect several measures of sexual behaviour. In summary, these data demonstrate that the oestrogen receptor is involved in the control of female copulatory behaviour. The androgen receptor plays a role in the expression of male, but not female, sexual behaviour. Female musk shrews display copulatory behaviour in advance of follicular development when oestradiol concentrations in plasma are very low. Thus, they may have evolved a strategy of aromatizing peripherally produced androgens in the brain to concentrate the oestrogen required for the expression of sexual behaviour.
摘要 本研究旨在验证以下假设：即雌性麝鼩的性行为受睾酮向雌激素的神经芳香化作用调控。实验中，首先对去卵巢动物进行了皮下激素植入，其中包含可芳香化雄激素（睾酮或雄烯二酮）、不可芳香化雄激素（二氢睾酮或甲基三烯龙）或胆固醇。与对照组（胆固醇）相比，只有接受可芳香化雄激素的雌性动物表现出大量的性行为。为了研究雌激素受体的作用，向完整卵巢或接受睾酮处理的去卵巢雌性动物给予抗雌激素他莫昔芬（200 或 400 微克/天）。与对照处理相比，他莫昔芬处理对雌性性行为和几种外周组织的重量均有显著的负面影响。进行了类似的一组实验，以检查抗雄激素对雌性性行为的影响。雄激素受体阻滞剂氟他胺对性行为或外周组织重量均无影响。为了确定氟他胺在该物种中是否可以作为一种抗雄激素，在雄性麝鼩中进行了最后两项实验。氟他胺处理确实影响了雄性的几种性行为指标。总之，这些数据表明，雌激素受体参与了雌性交配行为的控制。雄激素受体在雄性性行为的表达中起作用，但在雌性性行为的表达中不起作用。雌性麝鼩在血浆中雌二醇浓度非常低的情况下表现出交配行为，这表明它们可能已经进化出一种策略，即将外周产生的雄激素在大脑中芳香化，以集中表达性行为所需的雌激素。
