Effects of the anti-androgen cyproterone acetate on the uptake of 1,2-3H-testosterone in neural and peripheral tissues of the castrate male rat.

Abstract

The anti-androgen cyproterone acetate (CA) causes regression of the seminal vesicle when administered to the mature male rat, and CA treatment of the pregnant rat permits vaginal development in male offspring. CA, however, does not inhibit androgen controlled sexual behavior in male rats. It was therefore hypothesized that CA might inhibit the uptake and retention of l,2-3H-testosterone in peripheral genital tissues, but not in central neural tissues which mediate mating behavior. To test this hypothesis, castrate males were administered tritiated testosterone following pretreatment with CA or oil and sacrificed 5 or 60 min after testosterone treatment. All tissue samples showed androgen uptake. CA had no influence on uptake measured at 5 min. In pituitary, brain and muscle, radioactivity levels were lower in the 60 min samples than in the 5 min samples. CA had no effect upon retention of testosterone measured at 60 min in these tissues. Radioactivity levels were the same or higher at 60 min in the seminal vesicle, glans penis and plasma samples. In these samples CA reduced radioactivity levels (seminal vesicle and glans penis) and heightened plasma radioactivity in the 60 min samples relative to the 5 min samples. Steroid separations showed that CA had its influence in those tissues which contain a significant amount of androstenedione. (Endocrinology 84: 217,1969)