硫酸铜和马度米星铵联合暴露对鲫鱼的毒性和效应标记物研究

Toxicity and Toxic Effect Markers of Combined Exposure of Copper Sulphate and Maduramicin on Carassius auratus

为探究硫酸铜和马度米星铵对水产动物的生态毒性,本研究以鲫鱼为模型,从急性毒性、亚急性毒性和遗传毒性3个方面研究硫酸铜和马度米星铵单一与联合暴露对鲫鱼的毒性效应。结果表明,硫酸铜对鲫鱼96 h的半数致死浓度(50%lethal concentration,LC_(50))为3.6 mg·L^(-1),硫酸铜和马度米星铵联合暴露时,硫酸铜对鲫鱼的96 h-LC_(50)为1.4 mg·L^(-1),马度米星铵对鲫鱼的96 h-LC_(50)为4.2 mg·L^(-1),硫酸铜对鲫鱼为高等毒性;硫酸铜和马度米星铵对鲫鱼的联合毒性表现为协同作用。染毒第7天,硫酸铜和马度米星铵均可影响过氧化氢酶(catalase,CAT)和谷胱甘肽过氧化物酶(glutathione peroxidase,GPx)的活性,随着剂量和染毒时间的增加,CAT和GPx的活性逐渐下降。硫酸铜和马度米星铵单一或联合暴露7 d或21 d显著下调cat基因表达,对sod和gpx基因表达无显著影响。染毒后期,染毒组谷丙转氨酶(alanine aminotransferase,ALT)、谷草转氨酶(aspartate transaminase,AST)和碱性磷酸酶(alkaline phosphatase,ALP)活性及丙二醛(malondialdehyde,MDA)含量均高于对照组。硫酸铜和马度米星铵单一及联合染毒均能诱导鲫鱼红细胞产生微核,微核数与硫酸铜和马度米星铵的浓度呈正相关;随着硫酸铜和马度米星铵浓度的增加,肝细胞的脱氧核糖核酸(deoxyribonucleic acid,DNA)出现断裂,彗星尾部所占比例逐渐升高;高浓度联合染毒组红细胞微核率和肝细胞尾部DNA百分比显著高于单一染毒组。硫酸铜和马度米星铵联合暴露可导致鲫鱼血液毒性、肝细胞氧化损伤及遗传毒性的加和性,为评估Cu^(2+)与马度米星铵复合污染对鲫鱼的生态毒性提供基础数据和理论依据。

To explore the ecotoxicity of copper sulphate and maduramicin on aquatic animals,Carassius auratus was used as an animal model to understand the acute toxicity,sub-acute toxicity and genotoxicity of single and combined exposure of copper sulphate and maduramicin.The results indicated that the 96 h 50%lethal concentration(LC_(50))of copper sulphate on Carassius auratus was 3.6 mg·L^(-1),when combined exposure,the 96 h-LC_(50) of copper sulphate and maduramicin were 1.4 mg·L^(-1) and 4.2 mg·L^(-1),respectively,suggesting high toxicity to Carassius auratus.The joint toxic effect of copper sulphate and maduramicin on Carassius auratus was synergistic.When copper sulphate and maduramicin were exposed for 7 d,activities of catalase(CAT)and glutathione peroxidase(GPx)in liver of Carassius auratus were elevated;with the increasing of exposure concentration and time,the activities of CAT and GPx were gradually decreased.Single and combined exposure of copper sulphate and maduramicin for 7 d and 21 d significantly decreased the expression of cat but no significant effect on sod and gpx.At 21 d,the activities of alanine aminotransferase(ALT),aspartate transaminase(AST)and alkaline phosphatase(ALP)as well as the content of malondialdehyde(MDA)in liver of Carassius auratus were significantly increased by copper sulphate and maduramicin treatment.Single and combined exposure of copper sulphate and maduramicin all induced micronucleus generation of red blood cells in Carassius auratus in a concentration-dependent manner.With increasing of copper sulphate and maduramicin concentration,deoxyribonucleic acid(DNA)of hepatocytes in Carassius auratus were broken,and the percentage of comet tails was increased gradually.Furthermore,the micronucleus rate and the percentages of comet tails of combined exposure group were significantly higher than single exposure group.In summary,combined exposure of copper sulphate and maduramicin induce additivity of hematotoxicity,oxidative damage of hepatocytes,and genotoxicity on Carassius auratus,which together provides foundation data and the theoretical basis for the evaluation of ecotoxicity of combined contamination of copper ions and maduramicin in Carassius auratus.