title: [Induction of free radicals after dietary exposure by mercury contaminated rice and protective effect of coexisting selenium].
abstract: Sprague-Dawley rats were reared by environmental mercury contaminated rice to survey the potential health risk of Wanshan mercury mining area. Electron spin resonance (ESR) was introduced to detect the species and the intensities of free radicals, using spin trap 5,5-dimethyl-1-pyrroline-N-oxide (DMPO). The results showed that the mercury-contaminated rice significantly increased the levels of free radicals and MDA in rat brain at 7 days (p < 0.05). ESR spectrums showed that the principal spin adducts resulted from the trapping of alkyl free radical (alphaH = 22.7 x 10(-4)T +/- 1.6 x 10(-4)T, alphaN = 15.5 x 10(-4)T +/- 0.5 x 10(-4)T), and hydroxyl radical. Levels of free radicals and MDA increased slowly until after 90-day exposure period (83%, 100%). Element correlation analysis showed high correlations of mercury and selenium in the brain of rat fed with Wanshan rice, suggesting that the coexisting selenium in rice exhibited antagonistic effects on both mercury accumulation and toxicity. The slight increases of free radicals in rat brain at 7, 20 and 30-day exposure periods should be related with the scavenger effect of Se.
authors.affiliation: School of Environmental Science and Engineering, Donghua University, Shanghai 200051, China. ling-jx@dhu.edu.cn
authors.forename: Xiu-ling
authors.initials: XL
authors.lastname: Ji
authors.forename: Jin-ping
authors.initials: JP
authors.lastname: Cheng
authors.forename: Wen-hua
authors.initials: WH
authors.lastname: Wang
authors.forename: Li-ya
authors.initials: LY
authors.lastname: Qu
authors.forename: Xiao-xiang
authors.initials: XX
authors.lastname: Zhao
authors.forename: Hui-sheng
authors.initials: HS
authors.lastname: Zhuang
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy; D005506:Food Contamination; D005609:Free Radicals / Q000378:metabolism; D008315:Malondialdehyde / Q000378:metabolism; D008628:Mercury / Q000378:metabolism* / Q000633:toxicity; D008906:Mining; D012275:Oryza / Q000737:chemistry*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012643:Selenium / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D005609:Free Radicals; D008315:Malondialdehyde; D008628:Mercury; D012643:Selenium