Objective To investigate the androgen antagonists mechanisms in the rat of soy isoflavones in vivo,and also to study the relationship of dose-response.Method HERSHBERGER assay was carried out in immature male SD rats at the age of 4-5 weeks old,0.2,0.5,1.5 and 4.5 g/kg soy isoflavones,and 3.0 mg/kg flutamide as positive control,0.4 mg/kg Testosterone Propionate(TP).which was given to every groups,as negative control,vehicle as blank control,all groups were administered orally for 10 consecutive day.In the e...