Gilbert M M, Sprecher J, Chang L W, Meisner L F
J Toxicol Environ Health. 1983 Oct-Dec;12(4-6):767-73. doi: 10.1080/15287398309530468.
The cytogenetic effects of methylmercury (MeHg) producing chromosomal breakages, C-mitosis, and sister chromatid exchange are well documented. The present investigation was to determine whether vitamin E, which has been shown to exert a certain protective measure on the nervous system of animals exposed to methylmercury, also will diminish the genotoxicity of MeHg. Adult hamsters were given a daily injection (ip) of methylmercury chloride at a dosage of 2.0 mg/kg body weight (kg b.w.) and/or with 2.0 mg/kg b.w. vitamin E for 3 wk. All animals were sacrificed 5 d after the last day of MeHg exposure. Fibroblast cultures were established with cells obtained from skins of these animals. Chromosome preparations were made from these cultures and evaluated, using a double-blind system, for incidences of chromosomal breakage. It was found that all the fibroblast cultures grew well except from those animals treated with MeHg. Furthermore, while the saline control and vitamin E alone cultures showed no significant number of chromosomal breakages, cells from animals treated with only MeHg showed a high incidence of chromosomal damage (50% with 1 break and 15% with 2 or more breaks). Such chromosomal damage, however, was totally eliminated by vitamin E treatment (no chromosomal breakage was observed in cultures from MeHg/vitamin E animals). Our present study represents the first report on in vitro chromosomal damages as a result of in vivo MeHg exposure. Furthermore, our investigation also demonstrated the protective potential of vitamin E against genotoxicity of methylmercury.
甲基汞（MeHg）可导致染色体断裂、C-有丝分裂和姐妹染色单体交换，其细胞遗传学效应已有充分记载。本研究旨在确定已被证明对暴露于甲基汞的动物神经系统有一定保护作用的维生素E，是否也能降低MeHg的遗传毒性。成年仓鼠每天腹腔注射2.0毫克/千克体重（kg b.w.）的氯化甲基汞和/或2.0毫克/千克体重的维生素E，持续3周。在停止暴露于MeHg的最后一天后5天，处死所有动物。用从这些动物皮肤获取的细胞建立成纤维细胞培养物。从这些培养物中制备染色体标本，并采用双盲系统评估染色体断裂的发生率。结果发现，除了用MeHg处理的动物外，所有成纤维细胞培养物生长良好。此外，生理盐水对照组和仅用维生素E处理的培养物未显示出明显数量的染色体断裂，而仅用MeHg处理的动物的细胞显示出高发生率的染色体损伤（50%有1处断裂，15%有2处或更多处断裂）。然而，维生素E处理完全消除了这种染色体损伤（在MeHg/维生素E处理的动物的培养物中未观察到染色体断裂）。我们目前的研究是关于体内暴露于MeHg导致体外染色体损伤的首次报道。此外，我们的研究还证明了维生素E对甲基汞遗传毒性的保护潜力。
