Implantation of dihydrotestosterone propionate into the lateral septum inhibits sexual receptivity in estrogen-primed, ovariectomized rats.

Abstract

Two experiments were conducted to identify sites in the female rat brain at which dihydrotestosterone acts to inhibit estradiol-induced feminine sexual behavior. 27 gauge cannulae containing either crystalline dihydrotestosterone propionate (DHTP) or cholesterol were implanted unilaterally into the lateral septum, preoptic area-anterior hypothalamic area, ventromedial nucleus of the hypothalamus or caudate putamen. In experiment 1, rats were given stereotaxic implants of steroids prior to being injected daily with estradiol benzoate (EB; 0.5 microgram/100 g body weight) and tested for sexual receptivity. In experiment 2, animals were injected daily with EB (0.9 microgram/100 body weight) and tested for sexual receptivity prior to and after stereotaxic implantation of steroids. In both experiments significant reductions in lordotic behavior were obtained only with lateral septal implants of DHTP.