环境汞污染粮食长期暴露对大鼠脑神经递质的影响

为了探讨环境汞污染暴露对公众健康的潜在危害,采用汞矿地区环境汞污染粮食对大鼠进行长期暴露试验,研究不同暴露时间节点大鼠脑中神经递质乙酰胆碱(ACh)及其水解酶乙酰胆碱酯酶(AChE)的变化情况,并以市售上海粮食作对照.结果表明,环境汞污染粮食暴露7d后,大鼠脑中神经递质ACh出现显著升高;暴露30d后仍维持在较高水平.长期暴露90d后,脑中ACh出现了显著的回落.AChE的变化则与之相反.饲喂过程中,粮食中的硒对汞的蓄积及毒性有一定的拮抗效应.实验结果表明,实地环境汞污染粮食长期暴露后对大鼠表现出明显的神经毒性作用.环境汞污染长期暴露引起的ACh含量下降,AChE活力上升是否与阿尔茨海默病(AD)有关值得注意.

Effect of Chronic Exposure by Mercury Contaminated Rice on Neurotransmitter Level Changes in Rat Brain

In order to survey the potential health risk of environmental exposure by mercury,Sprague-Dawley rats were reared by mercury contaminated rice from mercury mining area.The changes of neurotransmitter acetylcholine(ACh) and acetylcholinesterase(AChE) in rat brain were examined at different times.The results show that the mercury-contaminated rice significantly increase the content of ACh in rat brain after exposure for 7 days.ACh maintained at a high level even after exposure for 30 days,but decreased significantly after exposure for 90 days.The changes of AChE represented an inverse trend compared with that of ACh.The coexisting selenium in rice exhibited antagonistic effects on both mercury accumulation and toxicity.The findings suggested that neurotoxic effects of environmental mercury contamination had been significantly represented after chronically dietary exposure.Further studies are needed to examine the relationship between the neurotransmitter level changes and the Alzheimer's Disease(AD).