Activation of intermale aggression by combined estrogen-androgen treatment

Adult CD-1 male mice were gonadectomized and tested for their response to the aggression-promoting property of androgens, estrogens, or combined androgen-estrogen treatment. The results showed that the combined treatment was the most effective, although androgens alone were sufficient for behavioral restoration. These findings suggest that testosterone may activate aggression through both its androgenic and estrogenic metabolites.