NEUROENDOCRINE MECHANISMS REGULATING DIMORPHIC BEHAVIORS

描述（申请人的摘要）：长期以来已知睾酮（T）可以促进男性典型和女性典型的生殖行为。 然而，T影响这两种行为的机制尚未完全理解。本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）T在大脑中转化为行为相关的代谢物雌激素（E）和双氢睾酮（DHT）; 3）大脑对T和代谢物的敏感性。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转换的研究中。预测在男性中应加强与男性行为相关的因素，在女性中应加强与女性行为相关的因素。此外，在繁殖行为也具有性二态性的物种中，这些因素的性二态性应得到加强。第一个实验将确定男性和女性血液中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，将通过检查T受体的分布以及T代谢物E和DHT的受体来确定大脑对T的敏感性的性别差异。

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.