Expression of prostatic glutathione-peroxidase (GSH-PO) in the rat treated with a combination of testosterone and 17beta-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 activity, and lipid peroxide (Thiobarbituric acid: TBA) value in the ventral prostate were investigated. Male Crj: CD (SD) IGS rats were divided into six 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 testosterone daily for three- or seven-day administration two days after castration, respectively. In groups 5 and 6, rats were subcutaneously administered 1 mg/animal of testosterone plus 0.01 mg/animal of 17beta-estradiol (E2) daily for three- or seven-day administration two days after 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 level of testosterone plus E2-treated animals was higher than that of testosterone-treated animals. These findings strongly suggest that expression of GSH-PO in the rat ventral prostate is testosterone- or E2-dependent. We speculate that the transcription of prostatic GSH-PO mRNA was regulated by testosterone or E2 and de novo synthesis of GSH-PO would thus be regulated at transcription level by testosterone or E2.
Murakoshi
Masanori
M
Safety Research Department, Teikoku Hormone Mfg. Co., Ltd., Tokyo, Japan.
Ikada
Rie
R
Tagawa
Masashi
M
D000818:Animals; D004334:Drug Administration Schedule; D004338:Drug Combinations; D004958:Estradiol / Q000008:administration & dosage*; D005979:Glutathione Peroxidase / Q000235:genetics / Q000378:metabolism*; D007279:Injections, Subcutaneous; D008297:Male; D009919:Orchiectomy; D011467:Prostate / Q000201:enzymology*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D013739:Testosterone / Q000008:administration & dosage*
D004338:Drug Combinations; D012333:RNA, Messenger; D013739:Testosterone; D004958:Estradiol; D005979:Glutathione Peroxidase