EXPRESSION OF GLUTATHIONE PEROXIDASES IN THE ADULT MALE-RAT REPRODUCTIVE-TRACT

Objective: To evaluate the messenger RNA (mRNA) expression of three gl utathione peroxidase isoforms in the male reproductive tract and to fu rther characterize testicular glutathione peroxidase expression. Desig n: Analysis of glutathione peroxidase levels in untreated animals. Int ervention(s): P-32-labeled DNA probes were derived from known compleme ntary DNA (cDNA) sequences for classic cellular glutathione peroxidase , phospholipid hydroperoxide glutathione peroxidase, and secretory epi didymal glutathione peroxidase, and used to evaluate mRNA levels in ea ch tissue by Northern blot hybridization. Main Outcome Measure(s): Glu tathione peroxidase mRNA concentrations. Result(s): A 0.8-kb transcrip t was identified in liver, testis, prostate, seminal vesicle, vas defe rens, and epididymis using the cDNA probe for classic cellular glutath ione peroxidase. Using the probe for phospholipid hydroperoxide glutat hione peroxidase, a 0.9-kb transcript was identified in the epididymis , vas deferens, prostate, seminal vesicle, and Liver. In the testis, t he phospholipid hydroperoxide glutathione peroxidase transcript was hi ghly abundant and longer, measuring 1.1 Bb. The phospholipid hydropero xide glutathione peroxidase mRNA transcript was expressed in 40-, 60-, and 90-day-old rat testes, but was undetectable in testes of 10- and 20-day-old rats. Epididymal glutathione peroxidase was detected as a s ingle 1.9-kb transcript in the caput epididymis only. Conclusion(s): M ale rat reproductive tissues express at least three different isozymes of glutathione peroxidase. Phospholipid hydroperoxide glutathione per oxidase and classic cellular glutathione peroxidase are primarily foun d in testis, whereas epididymal glutathione peroxidase is expressed in the epididymis. (C) 1997 by American Society for Reproductive Medicin e.