水体重金属在斑马鱼(Danio rerio)组织中的累积及对抗氧化系统的影响---以浑河为例

目的]评估浑河水体重金属污染现状及其对水生生物生态健康的影响。方法]取浑河水样测定重金属元素含量(Al、Cr、Cu、Fe、Mg、Mn、Zn),并选择模式生物斑马鱼暴露浑河水90 d,测定水体重金属在斑马鱼脑、鳃、肝、肠、肌肉组织中的累积及对超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、还原性谷胱甘肽(GSH)、谷胱甘肽-S-转移酶(GST)、脂质过氧化产物(MDA)、乙酰胆碱酯酶(ACh E)、总抗氧化能力(T-AOC)以及Na~+/K~+-ATPase活性的影响。结果]浑河水重金属元素含量虽符合国家Ⅱ类水标准,但与对照组相比,Cu、Fe、Mn、Zn含量分别高出42.9%、217.2%、77.8%和96.2%。浑河水胁迫下的斑马鱼脑、鳃、肝、肠、肌肉组织中,重金属呈现不同程度的累积,其中肝组织的累积量最高。同时,肝组织中SOD和CAT增加率分别为109.1%和32.0%,而T-AOC显著下降28.5%,说明肝组织抗氧化能力下降。鳃组织中MDA显著升高59.2%,表明水体重金属引起脂质过氧化,诱导了斑马鱼鳃组织的氧化损伤。结论]斑马鱼肝鳃组织较为敏感,SOD、CAT、T-AOC及MDA可作为敏感的毒理学研究的生物标志物,对水体综合毒性进行早期预警。

Accumulation of Heavy Metal in Water in Zebrafish(Danio rerio)Tissues and Its Effects on the Antioxidant System:A Case of Hunhe River in Shenyang Section

Objective]The aim was to assess the status of heavy metal pollution of Hunhe River and its ecological health impact on aquatic or-ganisms.Method]The content of heavy metal elements like Al,Cr,Cu,Fe,Mg,Mn and Zn was determined.The model organism zebrafish were exposed to Hunhe River for 90 days,and the accumulation of heavy metal and the concentrations of superoxide dismutase(SOD),catalase (CAT),glutathione(GSH),glutathione-S-transferase(GST),lipid peroxidation(MDA)and acetylcholinesterase(AChE),total antioxidant ca-pacity(T-AOC)and Na +/K +-ATPase activity were determined in the brain,gill,liver,intestine and muscle tissue of zebrafish.Result]The heavy metal elements in the Hunhe River were in line with the national standards ofⅡlevel,but compared with control group,the concentration of Cu,Fe,Mn,zinc element was increased by 42.9%,217.2%,77.8% and 96.2%,respectively.Different accumulation degrees in the brain,gill, liver,intestine and muscle tissues of zebrafish under the stress of Hunhe River,and the highest accumulation was in liver tissue.At the same time, the increasing rate of SOD and CAT in liver tissue was 109.1% and 32.0%,respectively,while T-AOC was decreased significantly at the rate of 28.5%,indicating that the antioxidant capacity of liver tissue decreased.MDA was significantly increased at the rate of 59.2%in gill tissue,indi-cating that heavy metal in water induced lipid peroxidation and induced oxidative damage in gill tissues of zebrafish.Conclusion]The results show that liver and gill tissues of zebrafish were sensitive,and SOD,CAT,T-AOC and MDA can be used as sensitive biomarkers for toxicological research,and early warning of integrated toxicity of water.