镉对背角无齿蚌鳃组织抗氧化酶活性的影响

摘要

To select the appropriate biomarkers to indicate the degree of cadmium contamination in water bodies,in this study,we used A nodonta woodiana as experimental animal and set two Cd2+ treatment groups (0.337,1.349 rag/L) and one control group.The activities of superoxide dismutase (SOD),glutathione peroxidase (GPx) and catalase (CAT) in gill tissues were detected.The results showed that after the exposure of Cd the SOD activity was inhibited and GPx was induced in both high and low Cd2+ group,and the CAT activity was inhibited in the low Cd2+ group,but induced in the high Cd2+ group.After the elimination of Cd,the activity of SOD remained to be inhibited,and the activity of GPx was still induced.The CAT activity was recovered to control group level.Thus,Anodonta woodiana had a certain ability to recover from Cd2+ exposure.Also,the change of antioxidant enzyme activity could be used as a biomarkers to reflect the degree of organism being contaminated.%为了筛选合适的生物标志物以指示水体镉(Cd2+)的污染程度,试验以背角无齿蚌(A nodonta woodiana)为材料,设置了2个Cd2+质量浓度组(0.337,1.349 mg/L)和1个对照组,分别检测了镉暴露(0～ 28 d)和镉清除(28～56 d)过程中,背角无齿蚌鳃组织超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GPx)和过氧化氢酶(CAT)活性.结果表明,Cd2+暴露后鳃组织SOD活性被抑制;GPx活性被诱导;CAT活性在低浓度组中表现为抑制,在高浓度组中表现为诱导.Cd2+清除后,鳃组织中SOD活性依然被抑制,GPx活性依然被诱导,而CAT活性恢复到对照组水平.说明背角无齿蚌对镉污染具有一定的清除能力,抗氧化酶活性的变化能够反映生物体受污染物胁迫的程度,其可作为生物标志物用于指示水体镉污染状况.