Serotonin transporter (SERT) mRNA and binding site densities in male rat brain affected by sex steroids

Abstract

Estrogen increases serotonin transporter (SERT) mRNA and binding sites in female rat brain. In order to determine whether changes in SERT are gender- and steroid-specific we have now carried out studies on adult male Wistar rats which were either intact or castrated (under halothane anesthesia) and injected with arachis oil, estradiol benzoate (EB), testosterone propionate (TP) or the non-aromatizable androgen, 5α- dihydrotestosterone (5α-DHT). The number of SERT mRNA-expressing cells in the dorsal raphe (DR) nucleus was decreased by castration and increased by treatment (for ~ 32 h) with EB or TP, but not 5α-DHT. Sex steroids had no effect on the number of SERT mRNA-expressing cells in the ..