Testosterone as well as estrogen increases serotonin(2A) receptor mRNA and binding site densities in the male rat brain

Abstract

Our previous findings in female rats suggest that the potent effects of sex steroids on mood and mental state may be mediated, in part, by the effect of estrogen on the 5-hydroxytryptamine(2A) receptor (5-HT(2A)R) in brain. The aim of the present study was to determine the effect of acute (~ 32 h) sex steroid manipulation on central 5-HT(2A)R in the adult male Wistar rat. Castration (under halothane anesthesia) decreased while testosterone or estrogen, but not 5α-dihydrotestosterone (5α-DHT), increased significantly the 5-HT(2A)R mRNA content in dorsal raphe nucleus and the density of 5-HT(2A)R binding sites in frontal, cingulate and primary olfactory cortex and nucleus accumbens. The lack o..