Pb~(2+)对建鲤幼鱼抗氧化酶活性和总抗氧化能力的影响

为了解铅对建鲤幼鱼(Cyprinus carpio var.Jian)的影响,将建鲤幼鱼暴露于不同水平(0、0.648、1.296、6.480 mg/L)的Pb2+水溶液中,于96 h分别测定建鲤幼鱼肝胰脏、肠、鳃、肌肉中的超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、过氧化氢酶(CAT)活性及总抗氧化能力(T-AOC)。结果表明:随着Pb2+浓度的升高,抗氧化酶活性升高,达到极值后下降。0.648 mg/L浓度组中,肝胰脏中抗氧化酶活性及总抗氧化能力均有较明显升高;肌肉中抗氧化酶活性及总抗氧化能力变化较小;在高浓度组(6.480 mg/L),肾中的三种抗氧化酶活性及总抗氧化能力仍在升高,而在其他组织中酶的活性有所降低。上述研究结果表明,与肠、鳃、肌肉、肾相比,肝胰脏中的抗氧化酶活性及总抗氧化能力敏感,是最先启用的主要解毒器官;在高浓度胁迫时,肝胰脏解毒能力下降,抗氧化防御作用的主要器官由肝胰脏转移到肾脏。

Effects of Pb2+ on activities of antioxidant enzymes and total antioxidant capacity of juvenile Cyprinus carpio var.Jian

Juvenile Cyprinus carpio var.Jian were exposed to Pb2+ at concentrations of 0、0.648、1.296、6.480 mg/L,and activities of superoxide dismutase(SOD),glutathion peroxidase(GSH-Px),catalase(CAT),and total antioxidant capacity(T-AOC) in hepatopancrease,intestines,gills and muscle were determined at 96h after the exposure during the acute toxicity test to understand the impacts of lead on juvenile C.carpio var.Jian.The results showed that:the activities of antioxidant enzymes and T-AOC increased with the increasing of Pb2+ concentration,then reduced after reaching peak.When fish was exposed to the concentration of 0.648 mg/L,the activities of antioxidant enzymes and T-AOC in hepatopancreas were significantly higher than that of control,while there were no significant differences in muscle.When fish were exposed to the concentration of 6.480 mg/L,the activities of antioxidant enzymes and T-AOC increased in kidney,but reduced in other tissues.These results suggest ed that:compared with intestines,gill,muscle and kidney,the activities of antioxidant enzymes and T-AOC in hepatopancreas were more sensitive.Hepatopancreas was the first detoxifying organ when stressed by Pb2+;when fish was exposed to high concentration,detoxifging ability of hepatopancreas reduced,and kidney became to the main detoxifying organ.