水体Hg^2＋对中华绒螯蟹（Eriocheir sinensis）血淋巴抗氧化酶活力和丙二醛含量的影响

摘要

采用单因子实验设计方法，进行了水体汞（Hg^2＋）在不同暴露时间对中华绒螯蟹血淋巴超氧化物歧化酶（SOD）、谷胱甘肽过氧化物酶（GPX）和过氧化氢酶（CAT）活力以及脂质过氧化产物丙二醛（MDA）含量的影响研究。结果表明，较低浓度Hg^2＋（0．01和0．05mg／L）处理组中华绒螯蟹血淋巴SOD、GPX、CAT活力在短时间内上升，表现出一种“毒物兴奋效应”；随着暴露时间的延长，三种酶酶活力均受到明显的抑制；高浓度的汞（0．20和0．30mg／L）无论暴露时间长短，对三种抗氧化酶均产生明显的抑制作用。本研究中不同浓度的Hg^2＋处理组中华绒螯蟹血淋巴MDA含量均高于对照组，表现出“剂量．效应”和“时间．效应”关系。双因素方差分析结果表明，水体Hg^2＋的暴露浓度和暴露时间均对中华绒螯蟹血淋巴三种抗氧化酶和MDA含量产生显著影响。血淋巴SOD、GPX、CAT活力以及MDA含量对水环境中的Hg^2＋反应灵敏，可作为中华绒螯蟹毒理学评价指标以及重金属污染监测指标。%The effects of mercury （Hg^2＋） on antioxidant enzymatic activity and MDA content in haemolymph of juvenile Chinese mitten crab, Eriocheir sinensis, were investigated. The results showed significantly increased in activities of superoxide dismutase （SOD）, glutathione peroxidase （GPX）, and catalase （CAT） in the groups treated with 0.01 and 0.05mg/L Hg^2＋ in a short period of time, which appeared as ＂Poison-intoxication effect＂; however, these antioxidant enzymes decreased in activities with increasing exposure time. In contrast, we found decreased enzyme activities in the presence of 0.20, and 0.3Omg/L Hg^2＋ regardless on the length of the exposure time. MDA content in haemolymph of crabs exposed to different Hg^2＋ concentrations were significantly higher than controls, which appeared as dose and time dependable. Two ways analysis of variance was determined and results showed that both concentration and exposure time of Hg^2＋ to these juvenile Chinese mitten crabs had significant effects on these three antioxidant enzymes activities and MDA content. Based on our study, SOD, GPX, and CAT activities and MDA content in haemolymph orE. sinensis were sensitive to ambient Hg^2＋ and could be used as biomarkers in evaluating the toxicity of mercury or any other heavy metals contamination to crustacean.