As(Ⅲ)暴露对紫贻贝抗氧化酶活性和脂质过氧化的影响

Study on the effects of As(Ⅲ) exposure on antioxidant enzymes and lipid peroxidation of Mytilus galloprovincialis

为探讨As(Ⅲ)对紫贻贝(Mytilus galloprovincialis)肝胰腺和鳃组织抗氧化能力的影响,测定了1、10、100μg/LAs(Ⅲ)暴露30天后,肝胰腺和鳃组织超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽巯基转移酶(GST)的活性变化以及谷胱甘肽(GSH)和丙二醛(MDA)含量的变化。结果发现:As(Ⅲ)暴露对紫贻贝肝胰腺CAT、SOD、GST活性以及GSH含量无显著影响,高浓度As(Ⅲ)暴露可诱导MDA含量的显著升高;对鳃组织而言,中等剂量暴露组CAT活性以及GSH含量较对照组水平极显著升高,高剂量As(Ⅲ)暴露组MDA含量较对照组也显著升高。研究结果表明,低浓度As(Ⅲ)长期暴露即可导致紫贻贝产生氧化胁迫,导致肝胰腺和鳃组织的脂质过氧化,且As(Ⅲ)对紫贻贝鳃组织的影响较肝胰腺组织更加显著。

In the present study,the antioxidant responses and lipid peroxidation in gills and digestive glands were determined to investigate subchronic toxic effects of sodium arsenite on Mytilus galloprovincialis.The mussels were exposed to different doses of sodium arsenite （1,10,100 μ g/L） respectively for one month,and the enzymatic activities of glutathioneS-transferase （GST）,superoxidase dismutase （SOD）,catalase （CAT） and the contents ofglutathione （GSH）,malondialdehyde （MDA） were measured.No significant change was observed in CAT,SOD,GST activities and GSH content of hepatopancreas after As （Ⅲ） exposure; however,MDA content was significantly increased in the high dose group compared to the control group.As for gills,the MDA content of high dose group increased significantly,and the CAT activity and GSH content of 10 μg/L As （Ⅲ） group increased significantly,comparing with those of the control group.These results indicated that sub-chronic exposure to low level of As （Ⅲ） could induce oxidative stress and lipid peroxidation in hepatopancreas and gills of M.galloprovincialis,and the response of gills was more sensitive than that of hepatopancreas.