亚硒酸钠对甲基汞中毒大鼠的影响研究

Effects of Sodium Selenite on Methyl Mercury Poisoned Rats

以4 mg/kg氯化甲基汞灌胃28天,建立SD大鼠甲基汞亚急性中毒模型。再给予高、中、低三个剂量的亚硒酸钠,选择补硒后0、30、60、90 d四个时间点进行研究。通过考察大鼠体重、生化指标、汞和硒在体内的分布与排出情况,来研究补充不同剂量、不同天数的硒对甲基汞中毒大鼠的影响。结果表明:对甲基汞中毒大鼠补硒后,可加快体重增长,且表现为低剂量组>中剂量组>高剂量组。与对照组相比,补硒30 d的肝脏GSH-Px(谷胱甘肽过氧化物酶)和60 d的血清GSH-Px显著升高,60 d的肝脏MDA(丙二醛)显著降低,对肾脏无明显影响。补硒组在补硒20 d内,会抑制尿液中汞的排出,高、中剂量组在60 d后可增加汞在脑和肝中的蓄积。试验证实硒对甲基汞中毒具有一定的解毒作用,可加快体重增长,降低肝脏的氧化损伤,以最大无作用剂量补充60 d为宜。

4 mg/kg of methyl mercury chloride was given to rats for 28 days to establish the sub - acute mercury poisoned rats model. Three different doses of sodium selenite were then given to the poisoned rats. The influence of dosage and time of selenium supplementation on body weight, biochemical indices, distribution and elimination of mercury and selenium in methyl mercury poisoning rats were studied after 0, 30, 60 and 90 days of selenium supplementing. Results showed that the weight increased faster in selenium supplementation group with an order of low dose group 〉 medium dose group 〉 high dose group. Comparing to the control group, the activities of GSH - Px in the livers at 30 days and in the serums at 60 days after selenium supplementation increased significantly. The concentrations of MDA in the livers at 60 days after selenium supplementation decreased significantly. There was no significant effect on the kidneys. Selenium could inhibit mercury excretion from urine in 20 days and increase the mercury accumulation in the brains and livers inhigh and medium dose groups at 60 days after selenium supplementation. It suggested that selenium had certain detoxification effect to methyl mercury poisoning, and could accelerate the weight gain and reduce the oxidative damage of liver. Application of maximum no effect dose for 60 days were recommended.