Abstract
Norethynodrel antagonized the fructose stimulating effects of exogenous testosterone in sex accessory organs of castrate mice. It was antiandrogenic at both low doses (50 [mu]g) and high doses (400 [mu]g) of testosterone. Norethindrone and ethisterone suppressed fructose formation in the testosterone-treated castrate mouse, but not as effectively as norethynodrel. Norethandrolone exerted no antagonistic activity.