Effects of short-term methylmercury exposure on metallothionein mRNA levels in the testis and epididymis of the rat.

摘要: Methylmercury (MeHg) is a widespread environmental contaminant that causes reproductive dysfunction in men. Metallothioneins (MTs) are low-molecular-weight proteins can bind heavy metals and protect the cell from metal toxicity. MT levels increased by exposure to physiological stressors. Although MTs have been identified testis epididymis, little known about their distribution regulation epididymis or effects of MeHg on male tissues. The objective this study was determine whether I, II, III mRNA present if relative differ between epididymal segments, alters cellular for segments rat. Northern blot analysis done total RNA isolated each four (initial segment [IS], caput [CT], corpus [CS], cauda [CA] epididymidis) using cDNA probe I II. transcripts were all segments. lowest observed IS; these 4-fold less than CT CS 5.5-fold CA. II similar IS but eightfold higher A generated reverse transcription-polymerase chain reaction testicular RNA. detected only not To assess levels, rats exposed 14 days one five doses (0, 25, 50, 100, 200 [microg/kg/day] via subdermal osmotic pump. No changes either body weight weights testis, seminal vesicles, ventral prostate MeHg-treated control rats. Serum testosterone significantly decreased at highest dose. In treatment resulted 2.5- 7-fold increases levels. There no initial 50 microg/kg/ day dose, whereas there significant differences lower 100 microg/kg/day also lower, with exception two doses, different controls tested. epididymidis, did alter group. dose-dependent manner up 63%. unaltered. Together data indicate adult modulate both Furthermore, following suggesting accumulation modulation.