BDE-47胁迫对双齿围沙蚕抗氧化防御系统的影响

摘要

将双齿围沙蚕 Perinereis aibuhitensis 暴露在 BDE-47下进行急性毒性试验，测定96 h-LC50。在此基础上，研究了暴露在0、2、4、8 mg·L－1的 BDE-47污染物下，双齿围沙蚕的谷胱甘肽（GSH）含量、谷胱甘肽过氧化物酶（GPx）活力、超氧化物歧化酶（SOD）活力、过氧化氢酶（CAT）活力以及丙二醛（MDA）含量、谷胱甘肽硫转移酶（GST）活力的变化情况。结果表明 BDE-47对双齿围沙蚕的96 h-LC50为31．24 mg·L－1。在暴露期间，与对照组比较，各处理组的 GSH 含量、GST 活力、CAT 活力总体上无显著变化，仅8 mg·L－1组的 GST 活力在14 d 极显著性升高（P ＜0．01）。暴露1 d 时，4 mg·L－1处理组 GPx 活力显著升高（P ＜0．05），在第7～14 d 时，2 mg·L－1处理组的 GPx 活性呈上升趋势；在 暴 露1 d 时，4 mg·L－1、8 mg·L－1两组的SOD 活力显著下降（P ＜0．05），整体上看，在1～7 d 时，SOD 活力被诱导升高。14 d 时，与对照组的比较，4、8 mg·L－1处理组的 SOD 活力分别被显著（P ＜0．05）和极显著（P ＜0．01）抑制。在暴露1 d 时，MDA 含量被诱导升高（P ＜0．05），且4 mg·L－1极显著升高（P ＜0．01）。在暴露4～14 d MDA 含量总体上无明显变化，仅第7 d 的8 mg·L－1处理组显著升高（P ＜0．05）。结论：在双齿围沙蚕抗氧化防御系统中，MDA 含量和 SOD 活力均在胁迫初期有显著变化，因此 MDA 含量和 SOD 活力可以作为潜在的生物标志物。%Perinereis aibuhitensis is used as biological subject in acute toxicity test,for determining the 96 h-LC50 of tetrabromodiphenyl ether(BDE-47).On this basis,the activities of SOD,CAT ,GST,GPx and the contents of GSH,MDA of the antioxidant defense system of Perinereis aibuhitensis exposed to 0,2,4,8 mg · L-1 of BDE-47 pollutants were determined.The results were as follows:the 96h-LC50 of BDE-47 to Perinereis aibuhitensis was 31.24 mg · L-1 . Compared with the control group,the content of GSH and activities of GST and CAT had basically no significant change, only the GST activity of 8 mg·L-1 group was significantly higher (P <0.01)on 14 th day.The GPx activity of 4 mg· L-1 group was significantly higher (P <0.05)on 1 th day,and 2 mg·L-1 group showed the increasing trend during the 7 th to 14 th day.On 1 th day,the SOD activity of the 4 mg·L-1 and 8 mg·L-1 groups significantly decreased (P <0.05). Overall,during the period of 1-7 d,SOD activity of the 2 mg·L-1 ,4 mg·L-1 groups were induced to rise. On 14 th day,SOD activity in 4 mg·L-1 ,8 mg·L-1 groups were significant (P <0.05)and significantly (P <0.01)inhibited respectively. The MDA content of all the treatment groups were induced to increase (P <0.05),and 4 mg·L-1 group significantly increased (P <0.01)on 1 th day. There was no significant change in the content of MDA of the treatment groups during the exposure period of 4-14 th day,only 8 mg·L-1 group was significantly higher (P <0.05)on 7 th day.In conclusion:the content of MDA and activity of SOD of the antioxidant defense system of Perinereis aibuhitensis had significant changes at the early exposure stage (P <0.05),which could be used as potential biomarkers.