Cu2+对羽摇蚊幼虫(Chironomus plumosus)口器致畸作用和抗氧化酶活性的影响

采用静水生物测试法研究Cu2+对羽摇蚊幼虫的急性毒性效应.设定0.005、0.010和0.020g·L-1 3个Cu2+浓度梯度进行急性暴露试验,分别于试验24、48、72和96h时测定摇蚊幼虫组织匀浆超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽-S转移酶(GST)的活性.结果表明,Cu2+对羽摇蚊幼虫体组织CAT和SOD有明显影响,表现出剂量-效应关系.GST活性在暴露72h后表现为受诱导作用(P＜0.05),并在96h时达到最高值(P＜0.01).对经0.005、0.010和0.020g·L-1 3个Cu2+浓度梯度刺激7d后摇蚊幼虫的口器致畸情况的研究结果表明,致畸率与Cu2+暴露浓度之间呈显著正相关关系(P＜0.05).

Effect of Copper on Antioxidant Enzymes Activity and Mouthpart Deformity of Chironomus plumosus

Acute toxicity of copper to larvae of Chironomus plumosus was studied by using the static-test method in the laboratory.The experiment was designed to have three levels of Cu2+ concentration,i.e.0.005,0.010 and 0.020 g·L-1.Superoxide dismutase(SOD),catalase(CAT) and glutathione S-transferase(GST) activities in the homogenate of tissues of the larvae were monitored after they were exposed to the substance for 24,48,72 and 96 h,separately.Results show that Cu2+ displayed significant effects on the activities of SOD and CAT,and such effects were significantly related to dosage of the substance.GST activity was induced after 72 h of exposure,and peaked after 96 h of exposure(P<0.01).The induction of mouthpart deformity and the developmental response with exposure to three concentrations(0.005,0.010 and 0.020 g·L-1) of copper for 7 days were investigated.It was found that teratogenesis of the larvae is significantly and positively related with Cu2+ concentration they are exposed to.