[Effect of glutathione and methionine on the distribution and methylic metabolism of arsenic speciation in mice exposed to arsenic through drinking water].

ABSTRACT

OBJECTIVE: To explore the effect of glutathione and L-methionine on the distribution and methylic metabolism of arsenic speciation in the liver, blood and kidney of mice exposed to inorganic As through drinking water. METHODS: Mice were randomly divided into control groups (Con), the only groups with arsenic (As group), GSH intervention groups (GSH) and L-Met intervention groups (L-Met). The mice of experimental groups were exposed to arsenite by drinking water at the concentration of 50 mg/L arsenite for 4 weeks. The GSH groups and the L-methionine groups were injected with glutathinone and L-methionine respectively on the fifth week. Livers, bloods and kidneys were taken to determinate the concentrations of inorganic (iAs), monomethylarsenic acid (MMA) and dimethylarsenic acid (DMA) using hydride generation trapping by ultra-hypothermia coupled with atomic absorption spectrometry. RESULTS: In liver, contents of DMA in L-methionine groups were moer higher than those of the As group. The primary methylic indexes (PMI) of arsenic speciation in the GSH groups and the secondary methylic indexes (SMI) of arsenic speciation in the GSH groups and L-methionine groups were more higher than those of the As group. In blood, contents of DMA and the total arsenic speciation (TAs) in both GSH groups and L-methionine groups were more higher than those of the As group. The PMI of arsenic speciation in both GSH groups and L-methionine groups were more higher than those of the As group. CONCLUSION: GSH and L-methionine could promote the methyee metabolism of iAs. As a result, the content of DMA, the end product of methylated metabolism of arsenic, rises, which facilitates the methylic metabolism and excretion of iAs.