Effects of Exogenous Methionine on Arsenical Distribution in Female Mice Exposed to Sodium Arsenite through Drinking Water / 环境与健康杂志

ABSTRACT

Objective To explore the effects of exogenous methionine on arsenical distribution in liver,blood and brain of mice exposed to sodium arsenite through drinking water. Methods The female Kunming mice were randomly divided into control group, the alone arsenic exposure group , the low level methionine intervention group, the moderate level methionine intervention group and the high level methionine intervention group, eight mice in each group . The mice in the experimental groups were exposed to sodium arsenite through drinking water at 50 mg/L arsenic for four consecutive weeks. And at the fourth week the 5 groups were treated intraperitoneally with saline solution (control and As group),100 mg/kg b.w,200 mg/kg b.w or 400 mg/kg b.w methionine,respectively . Twenty-four hours after cessation of methionine administration,mice were anaesthetized and rapidly dissected. The samples of blood,liver and brain were removed immediately for arsenic species analysis. Levels of inorganic arsenic (iAs),monomethylarsonic acid (MMA) and dimethylarsenic acid (DMA) were determined by HG-AAS method. Then total arsenic speciation( TAs), primary methylation ratio( PMR)and secondary methylation ratio( SMR)in each tissue were calculated. Results Compared with the control group, the levels of iAs, MMA, DMA and TAs in liver, brain and blood, were significantly higher in all experimental groups ( P