Distribution of gossypol.

Male rabbits and rats were administered gossypol (20 mg/kg/day) for 12 and 7 weeks respectively. Gossypol was estimated in different organs by the aniline method of Smith. Rat and rabbit spleen accumulated the highest level of gossypol. The lowest amount of gossypol was accumulated in the rabbit brain; the level of gossypol in rat brain was below the detectable limit of our method. Although rabbits were administered gossypol for 12 weeks, the accumulation of gossypol in rabbit testis was much lower than that of the rat testis. Our data suggest that non-sensitivity of rabbit to the antifertility effect of gossypol may be due to poor accumulation of gossypol in the testis. Negligible amount of gossypol in the brain rules out the possibility of involvement of hypothalamus-pituitary axis in the mechanism of action of gossypol on the testis.