铜对刀鲚幼鱼的急性毒性及对肝抗氧化酶活性与组织结构的影响  

Acute effects of copper on survival of fingerlings, antioxidant enzyme activities in liver and structure of gill and liver of Coilia nasus

作　　者：聂志娟[1] 徐钢春[1] 张守领[1] 徐跑[1] 顾若波[1] 

机构地区：[1]中国水产科学研究院淡水渔业研究中心,农业部淡水渔业和种质资源利用重点实验室,江苏无锡214081

出　　处：《中国水产科学》2014年第1期161-168,共8页Journal of Fishery Sciences of China

基　　金：农业部公益性行业科研专项(201203065);国家科技支撑计划项目(2012BAD26B05);江苏省科技支撑计划(农业)项目(BE2011411);江苏省水产三新工程重大专项(DZ2012-1)

摘　　要：采用静水生物测试法研究铜(Cu2+)对刀鲚(Coilia nasus)幼鱼的急性毒性并进行安全性评价。根据预实验结果,设定0.3、0.54、0.96、1.68和3 mg/L 5个CuSO4浓度梯度进行急性暴露实验,以肝组织超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性为指标,并通过观察肝、鳃组织病理变化来研究Cu2+污染对刀鲚幼鱼的毒性效应。结果表明,刀鲚幼鱼随Cu2+浓度升高毒性效应逐渐增强,24、48、72和96 h LC50分别为1.087、1.062、1.042和0.967 mg/L,安全质量浓度为0.009 67 mg/L。刀鲚幼鱼暴露24 h之后,各Cu2+浓度处理组(0.1,0.2,0.3 mg/L)CAT活性、SOD活性显著提高(P<0.05);暴露48 h后,各组CAT活性下降,CAT活性均低于对照组,下降幅度与Cu2+质量浓度呈正相关,SOD活性提高显著(P<0.05);暴露72 h后,SOD活性有所下降,SOD活性均低于对照组(P<0.05)。1.68 mg/L和3mg/L的Cu2+浓度对刀鲚幼鱼的鳃和肝都造成严重的损伤,暴露在高浓度组(3 mg/L)中的刀鲚,其鳃上皮细胞肿大变性,鳃小片几乎全部脱落;肝呈黄色,超微结构发现肝细胞明显增大,线粒体空泡化,胞质中出现空泡和大量脂滴,表明Cu2+可诱发刀鲚出现脂肪肝综合征。SOD、CAT活性变化以及鳃、肝结构变化都反映刀鲚幼鱼受伤害的程度,可用作安全性风险评价的参考依据。We evaluated the acute toxicity of copper on the survival rate of Coilia nasus fingerlings and on antioxidant enzyme （Superoxide dismutase, SOD; Catalase, CAT） activity changes in fish liver. The histology of experimental fish gills and liver were also analyzed. Fish were exposed to copper sulfate （CuSO4） solution with cue＋concentrations of 0（control）, 0.3, 0.54, 0.96, 1.68 and 3 mg/L. The 50% lethal concentration （LCs0） values of copper on C. nasus were 1.087, 1.062, 1.042 and 0.9 67 mg/L at 24, 48, 72 and 96 h, respectively. The safe concentration of copper for this spe- cies at the fingerling stage was calculated as 0.009 67mg/L. The activities of CAT and SOD were significantly enhanced in liver cells after the fish were exposed in CuSO4 for 12 and 24 h compared with those in the control group （P〈0.05）. Forty-eight hours later, the activities of CAT started to decline, while the activities of SOD did not decrease until 72 h. Overall, the CAT （after 48 h） and SOD （after 72 h） in the liver cells of fish exposed to copper sulfate exhibited lower activities than those in the control group. The changes of CAT activities after 48 h positively correlated with CuZ＋concentration. Our results indicated that 1.68 mg/L Cue＋was toxic to Coilia nasus fingerlings, resulting in swollen and denatured epithelium and deformed lamellae of the gills. The hepatic ultrastructural observation sampled from the fish exposed to 3 mg/L Cue＋showed significant hypertrophy of liver cells; the mitochondria exhibited vacuolization; vacuoles and lipid droplets occurred in cytoplasm. Copper appeared to induce fatty liver syndrome. We concluded that determining antioxidant enzyme （SOD and CAT） activities and histopathological analysis are important approaches to evaluate the safe concentration of copper for C. nasus fingerlings.

关 键 词：刀鲚幼鱼 铜 安全浓度 抗氧化酶 组织病理 

分 类 号：X171[环境科学与工程—环境科学]