The effects of new steroidal anti-androgen, TZP-4238, and chlormadinone acetate on the pituitary, prostate and adrenal gland of the rat: histopathological and immunocytochemical studies.

The atrophic effects of a synthetic steroidal anti-androgen, TZP-4238, on the pituitary, prostate and adrenal gland of rats were investigated. Male Sprague-Dawley rats were divided into three experimental groups. Group 1 consisted of controls. Groups 2 and 3 received chlormadinone acetate (CMA) 50 mg/kg/day and TZP-4238 10 mg/kg/day p.o., respectively, for 3 weeks. CMA (Group 2) produced marked atrophy of the prostate. Furthermore, CMA caused marked atrophy of the adrenal gland. Histopathologically, the remarkable atrophy was observed in the adrenal cortical cells of zonae fasciculata and reticularis. The most striking ultrastructural alterations were noted in the mitochondria. In addition, intramitochondrial localization of glutathione-peroxidase (GSH-PO) which effectively reduces the lipid peroxides, was less than that in the controls. In the anterior pituitary gland, CMA induced a reduction in the size of ACTH cells. TZP-4238 (Group 3) produced marked atrophy of the prostate. However, TZP-4238 exerted no effect on the adrenal gland or anterior pituitary ACTH cells. In addition, the present histopathological study showed that TZP-4238 or CMA exerted no effect on the testes or anterior pituitary LH cells. Therefore, it is suggested that TZP-4238 causes atrophy of the prostate without any significant histopathological changes in the adrenal glands or anterior pituitary ACTH cells under the present experimental conditions. We further speculated that TZP-4238 had a more potent anti-prostatic effect than CMA and TZP-4238 had a less inhibitory influence than CMA on the pituitary-adrenal axis.