IMMUNOLOCALIZATION OF GLUTATHIONE-PEROXIDASE (GSH-PO) AND BCL-2 IN THE RAT VENTRAL PROSTATE - EFFECTS OF CASTRATION AND ADMINISTRATION OF TESTOSTERONE

Immunolocalization of glutathione-peroxidase (GSH-PO), apoptosis and b cl-2 protein in the rat ventral prostate was investigated under the pr esence or absence of androgen. Male Sprague-Dawley rats were divided i nto four experimental groups. Group 1 consisted of intact controls. In group 2, rats were sacrificed two days after castration. In groups 3 and 4, rats were subcutaneously administered 1 mg/animal of testostero ne-propionate daily for three or seven days after two days of castrati on. The intensity of GSH-PO staining in the glandular epithelial cells of the ventral prostate was remarkably decreased after castration (Gr oup 2), and it was clearly recovered by testosterone-administration (G roups 3 and 4) to the castrated rats. The prostatic GSH-PO mRNA levels were diminished in the castrated rat ventral prostate but greatly inc reased by testosterone (Groups 3 and 4). Furthermore, castration (Grou p 2) induced apoptosis in the prostatic glandular epithelial cells and apoptosis was reduced by testosterone-administration (Groups 3 and 4) to the castrated rats. In groups 3 and 4, expression of bcl-2 protein was clearly detected in the glandular epithelial cells of the ventral prostate. These findings strongly suggest that expression of GSH-PO a nd bcl-2 protein in the glandular epithelial cells of the rat ventral prostate is considered to be testosterone-dependent.