RATS TREATED WITH A COMBINATION OF TESTOSTERONE AND 17f9-ESTRADIOL

In order to confirm the relationship between sex hormone administration and glutathione-peroxidase (GSH-PO) in the rat ventral prostate, the levels of GSH-PO mRNA, GSH-PO activitM and Iipid peroxide (TBA) value in the ventral prostate were investigated. Male Cij:CD(SD)IGS rats were divided into six experimental groups. Group 1 consisted o'f intact controls. In group 2, rats were sacrificed two days after castration. In groups 3 and 4, rats were subcutaneously administered 1 mglanimal of testosterone daily three or seven days after two ciays of castration, respectively. In groups 5 and 6, rats were subcutaneously administered 1 mg/animal of testosterone plus O.Ol mgfanimal of 17i/?-estradiol (E2) daily fbr three or seven days after two days of castration, respectively. GSH-PO activity of the ventral prostate homogenate for testosterone or testosterone plus E2 administration to the castrated rat was increased and the TBA value was remarkably decreased. The prostatic GSH-PO mRNA level was diminished in the castrated rat ventral prostate, but was increased by testosterone or testosterone plus E2 administration. In particular, the GSH-PO mRNA leve] of testosterone plus E2-treated animals was higher than that ol' testosterone-treated animals. These findings trongly suggest that expression of GSH-PO in the rat ventral prostate is considered to be testosteroncor E2-dependent. Furthermore, it is suggested that the transcription of prostatic GSH-PO mRNA was regu]ated by testosterone or E2 and de novo synthesis of GSH-PO would thus be regulated at transcription level by testosterone or E2.