Does the non-genomic effect of testosterone on social anxiety require the presence of a classical steroid receptor?

Steroid hormones may act through a rapid mechanism that does not require an intracellular steroid receptor and its effects on gene expression. In this study we have analysed this so-called non-genomic effect of testosterone on social anxiety in rats of both sexes using androgen and oestrogen receptor blockers. Male rats were divided into four groups: SHAM-CTRL (a sham operated group treated with oil as vehicle, n=10), SHAM-TST (a sham operated group treated with testosterone at a dose of 1 mg/kg, n=10), GDX-CTRL (a castrated group treated with oil, n=10) and GDX-TST (a castrated group treated with testosterone at a dose of 1 mg/kg, n=10). Female rats were divided into two groups: OVX-CTRL (an ovariectomized group treated with oil, n=10) and OVX-TST (an ovariectomized group treated with testosterone, n=10). The intracellular androgen receptor was blocked with flutamide and both intracellular oestrogen receptors were blocked with tamoxifen (a selective oestrogen receptor modulator). Rats were tested one hour after oil or testosterone administration in the social interaction test. Although the concentration of testosterone was higher in testosterone groups, no significant difference in social interaction was observed between the groups. In summary, in this first study focusing on the non-genomic effects of testosterone on social interaction no rapid effects of testosterone in adult rats were found. Further studies should analyse potential nongenomic effects of testosterone on other forms of social behaviour.