Cu^(2+)对黄河鲤的急性毒性

Acute Toxicity Study of Copper Exposure on Yellow River Carp(Cyprinus carrpio)

为了研究Cu2+对黄河鲤的急性毒性,采用静水暴露法,将黄河鲤暴露于不同质量浓度的Cu2+水溶液(0、0.08、0.16、0.32、0.63、1.26、2.51 mg/L)中,测定Cu2+对黄河鲤的安全质量浓度,Cu2+对黄河鲤肝胰脏抗氧化酶活性、组织病理变化的影响以及黄河鲤对Cu2+的富集情况。结果表明:Cu2+对黄河鲤为高毒物质;Cu2+对黄河鲤24 h、48 h、72 h、96 h的半致死浓度(LC50)分别为5.02 mg/L、2.77 mg/L、1.66 mg/L、1.12 mg/L,安全质量浓度为0.112 mg/L。肝脏为黄河鲤Cu2+富集的主要部位,其次为鳃、肾脏、肌肉。随着Cu2+质量浓度的增加,血液中的Cu2+含量呈现先升高后较平稳的趋势,而肝脏中的Cu2+含量整体上呈升高趋势。Cu2+对黄河鲤各组织均有明显的病理损伤,且随着Cu2+质量浓度的增加,病理损伤逐渐加重。其中肝脏表现为多发性溶解性坏死,鳃丝肿胀呈棒状。肝胰脏中的抗氧化酶(过氧化氢酶、总超氧化物歧化酶、铜-锌超氧化物歧化酶)活性随着Cu2+质量浓度的增加先升高后降低,而脂质过氧化产物丙二醛的含量持续增加。提示,Cu2+对黄河鲤可产生富集毒性,损伤黄河鲤的各个组织,其中肝胰脏中抗氧化酶可以作为生物标志物对Cu2+毒性进行评价。

In order to study the copper toxicity and tissue copper accumulation and elimination pattern on copper of Yellow River carp （ Cyprinus carpio ） , the Yellow River carp was tested in the static water to evaluate the safe concentration of copper, acute pathological changes, the change of antioxidant enzyme activity in liver,and the content of copper enrichment after exposed to copper 96 hours.Seven treatments （0,0.08,0.16,0.32,0.63,1.26,2.51 mg/L） in duplicate were tested.The results showed that copper stress was toxic on the Yellow River carp.The median lethal concentration of 24,48,72,96 h was 5.02 mg/L,2.77 mg/L,1.66 mg/L,1.12 mg/L.The 96 h safe concentration value was 0.112 mg/L.The concentration of copper in blood and muscle increased at first,then stably changed.But the concentration of copper in liver increased all the time, with the copper concentration increased.All tissues of Yellow River carp had pathological changes under copper stress and the pathological changes were more serious with the copper concentration increased.The changes contained the degeneratable necrotic foci in liver and sticks-like gill lamella hyperplasla.With the copper concentration increased,the activity of antioxidant enzyme（ CAT, T-SOD and Cu-Zn SOD ） in liver first rose, and then reduced.The content of lipid peroxidation product MDA in liver continued to rise.It was concluded that copper could not only produce toxicity of enrichment,but also damage all tissues of the Yellow River carp.The antioxidant enzymes in liver can be used as a biological marker to evaluate the toxicity of copper.