[Antiandrogenic effects of hydroxyniftolide in male rats]

Experiments on intact mature male Wistar rats showed the ability of hydroxyniftolide (4'-nitro-3'-trifluoromethyl-2-hydroxy-2-methylpropionylanilide), a hydroxylated antiandrogen derivative of niftolide, to inhibit the effects of male sex hormones in androgen target organs. At doses of 10 mg/kg and upwards administered intravenously or intramuscularly for 10 days, it stimulated the hypothalamohypophy-seogonadal system expressed in an increase in the activity of delta 5-steroid-3 beta-ol-dehydrogenase in the testicles and blood plasma testosterone concentration. Comparative studies on antiandrogenic properties of niftolide and hydroxyniftolide made it possible to show that the effect of the first agent was more noticeable with relation to the hypothalamic centers of gonadotropin secretion regulation whereas the effect of the second one was more noticeable in the accessory sex glands.