This is an application to provide the applicant released time from a heavy load of administrative and teaching duties so that she may further her research career. An award will allow her to devote more time to her federally-sponsored research on hormonal specificity and the activation of behavior and to obtain the additional training in modern biochemical techniques she needs to carry out this research. It will also provide time for additional behavioral research and to explore new areas for future research. Her plans for professional growth during the award period include the establishment of an independent biochemistry lab, continued collaboration with some of the pioneering researchers in behavioral endocrinology and biochemistry, continued research training of students and the addition of postdoctoral training, active participation in federal grant review, and attendance at specialized symposia. The primary goal of her research is to gain a better understanding of the physiological mechanisms underlying hormonal control of behavior. The behavioral actions of androgens such as testosterone appear to be mediated by the interaction of their estrogenic and androgenic metabolites. The major focus of the present research is to determine how these two classes of hormones interact within the brain to elicit such behaviors. Levels and turnover of four monoaminergic neurotransmitters, as well as levels of the enzymes responsible for the synthesis and degradation of a fifth neurotransmitter, acetylcholine, will be monitored in specific brain nuclei known to mediate behavior dependent on the combined actions of estrogens and androgens. Examining the responses of these neurotransmitter systems to treatment with androgens, estrogens, or combined treatment with both hormones should help us to understand how these two classes of hormones interact in the brain to modulate behavior. Interactions of the androgen and estrogen receptor systems in the same nuclei will also be examined. A second line of research investigates whether conversion of androgens to 5 -reduced metabolites is obligatory for the neutral activation of male behavior patterns. A third line of research investigates the importance of estrogenic metabolites in the bloodstream, their biological activity and binding to serum proteins, and examines whether social interactions affect the production rate of estrogenic metabolites from androgens.