NEUROENDOCRINE MECHANISMS REGULATING DIMORPHIC BEHAVIORS

说明(申请人摘要)：很早就知道，睾酮(T)可以促进男性典型的生殖行为和女性典型的生殖行为。然而，T影响这两种行为的机制尚不完全清楚。这项研究的目的是在三个不同的水平上进一步研究这些机制：1)T的循环水平；2)大脑中T转化为与行为相关的代谢物雌激素(E)和双氢睾酮(DHT)；3)大脑对T及其代谢物的敏感性。为了测试这些机制和特定生殖行为之间的关系是否延伸到其他物种，第二个物种将被纳入T转换的研究。预测男性应加强与男性行为相关的因素，女性应加强与女性行为相关的因素。此外，在生殖行为也是性别二型性的物种中，应该加强这些因素中的性别二型性。第一个实验将确定男性和女性血液中的T水平是否存在性别差异。第二个实验将测量男性和女性大脑中将T转化为E和DHT的酶的活性。最后，大脑对T的敏感性的性别差异将通过检查T受体以及T代谢物E和DHT的受体的分布来确定。

DESCRIPTION (Applicant's abstract): It has been long known that testosterone (T) can facilitate both male-typical and female- typical reproductive behaviors. However, the mechanism by which T affects both types of behavior is not yet fully understood. The objective of the proposed study is to further investigate these mechanisms at three different levels: 1) circulating levels of T; 2) conversion of T in the brain into the behaviorally-relevant metabolites estrogen (E) and dihydrotestosterone (DHT); 3) sensitivity of the brain to T and the metabolites. To test if the relationship between these mechanisms and specific reproductive behaviors extends to other species, a second species will be included in the study of T conversion. It is predicted that factors relevant to masculine behaviors should be enhanced in males, and factors relevant to female behaviors should be enhanced in females. Furthermore, a sex dimorphism in the factors should be enhanced in species whose reproductive behaviors are also sexually dimorphic. The first experiment will determine if a sex difference exists in T levels in the blood of males and females. The second experiment will measure the activity of the enzymes that convert T into E and DHT in the brain of males and females. Finally, sex differences in sensitivity of the brain to T will be determined by examining the distribution of T-receptors, as well as the receptors for the T metabolites, E and DHT.