title: Inhibitory effect of α-tocopherol on methylmercury-induced oxidative steress.
abstract: OBJECTIVE
  The present study investigated the involvement of oxidative stress in the degeneration of the cerebellum during methylmercury (MeHg) intoxication and the protective effect of α-tocopherol (Vit E) against MeHg toxicity.
  
  
  METHODS
  After 5 mg/kg of MeHg was administered to Wistar rats for 12 consecutive days, the cerebellum were examined histopathologically. In addition, the same amount of MeHg was administered to 3 different groups of Wistar rats: rats with a Vit E-deficient diet, rats fed 150 mg/kg of Vit E for 20 consecutive days after initial MeHg administration, and rats with an ordinary diet.
  
  
  RESULTS
  Positive immunoreactivity against anti-hydroxynonenal (HNE), a marker of lipid peroxidation, was observed in the cerebellum after MeHg administration. Levels of thiobarbituric acid reactive substance (TBARS), another marker of lipid peroxidation, and those of protein carbonyl, a biomarker for protein oxidation, increased after MeHg administration. In the rats with MeHg and a Vit E-deficient diet, mortality and prevalence of piloerection significantly increased, and in the rats with MeHg and Vit E, mortality, piloerection, retracted and crossed hind leg, and ataxic gait significantly decreased, compared with the rats with MeHg alone. The levels of NO(2) (-) and NO(3) (-) in the serum significantly increased in the rats with MeHg alone 14 days after the initial MeHg administration, but were significantly suppressed by Vit E administration.
  
  
  CONCLUSIONS
  Oxidative stress, especially lipid peroxidation, may play an important role in the cerebellar degeneration process during MeHg intoxication and Vit E may play a protective role against MeHg toxicity as an effective antioxidant.
authors: Department of Neurology, Graduate School of Medical Sciences, Kumamoto University, Kumamoto, Japan.
authors: Taro
authors: T
authors: Yamashita
authors: Yukio
authors: Y
authors: Ando
authors: Masaaki
authors: M
authors: Nakamura
authors: Konen
authors: K
authors: Obayashi
authors: Hisayasu
authors: H
authors: Terazaki
authors: Katsuki
authors: K
authors: Haraoka
authors: Sun Xu
authors: SX
authors: Guo
authors: Mitsuharu
authors: M
authors: Ueda
authors: Makoto
authors: M
authors: Uchino