The object of this study was to evaluate the effects of lixivium from ooze mud in the Changjiang estuary on antioxidant detoxifying enzymes activity in muscles of Exopalaemon carinicauda Mysis larvae and expressions of relative genes. The mysis larvae were exposed to different the volume ratio of lixivium from ooze mud and natural seawater levels:0 (natural seawater or control), 1∶4, 1∶2, 1∶1 and 1.5∶1 for 20 d and sampled randomly at 0 d,10 d and 20 d. The results indicated that in order to reduce the harm to the organism, antioxidant detoxifying enzymes like CAT and GST were response to overcome harmful environment and preventing toxicosis after forced by the lixivium from oonze mud. When Mysis larvae were exposed the lixivium, the activity of CAT would significantly rise in muscles. The concentration of the lixivium had significant positive correlation with the activity of CAT. Moreover, the activity of GST would significantly rise in 10 d, while the active was inhibited in 20 d. The dose-response relationship was not obvious. Detected the mRNA expression level of CAT, GST and HSP70, we found that the CAT, GST and HSP70 expression level in muscles of Exopalaemon carinicauda mysis larvae was all increasing in 10 d, while the expression level was decreasing in 20d. There was synchronization between the changes of enzyme activities of CAT and mRNA expression level changes of relative genes.%以脊尾白虾( Exopalaemon carinicauda)糠虾幼体为实验材料，研究底泥浸出液对抗氧化解毒酶和基因表达的影响。用长江口水域的底泥浸出液与过滤海水按等比例间距稀释成4个体积浓度水平（1∶4，1∶2，1∶1，1.5∶1），以过滤海水为对照组，每一个浓度组设3个平行样本，进行20 d的毒性实验。结果表明：实验进行20 d，底泥浸出液对糠虾幼体肌肉组织CAT酶活性有一定的诱导作用，浸出液浓度与CAT酶活性表现出正相关的剂量效应关系。实验开始10 d，不同浸出液胁迫下，GST酶活性均出现增加受到诱导，实验20 d后，GST酶活性下降受到抑制作用，但不同浸出液浓度胁迫下抑制和诱导效应关系不明显。虾类肌肉组织3种基因（CAT、GSTD和HSP70）表达量基本都表现为实验开始10 d时升高，而实验20 d后表达量下降，仅为10 d数值的百分之一左右，表明底泥浸出液对CAT、GSTD和HSP70的3种基因的mRNA转录水平表达在一定时间内有一定的诱导作用，但胁迫时间过长时，则产生较明显的抑制作用。
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