Figure 1. Animal models for studying sex hormone effects.
a) Administration of androgens (e.g. testosterone propionate) to females, and androgen receptor antagonist (e.g. flutamide) to males during perinatal period. This model allows for the investigation of organizational effects of gonadal hormones without affecting sex chromosomes or the gonadal status. b) Surgical removal of ovaries from XX females and testes from XY males. This model allows for the investigation of activational effects of gonadal hormones without altering the sex chromosomes or the organizational effects of gonadal hormones.