三丁基锡(TBT)对褐菖鲉肝脏抗氧化系统的影响

Abstract

使用环境浓度水平[1、10、100 ng（Sn）/L]的三丁基锡（tributyltin,TBT）对褐菖鲉进行水体暴露,观察TBT对褐菖鲉肝脏抗氧化防御系统的影响.暴露50 d后,10、100 ng/L组丙二醛含量的上升指示了环境浓度水平的TBT能够导致肝脏氧化胁迫.10、100 ng/L组的谷胱甘肽过氧化酶、超氧化物歧化酶和10 ng/L组的过氧化氢酶活性在TBT暴露50 d后被显著诱导.还原型谷胱甘肽含量在10、100 ng/L TBT暴露7 d后被显著诱导,而在暴露50 d后被浓度依赖性地抑制.TBT暴露7 d后,谷胱甘肽硫转移酶在10、100 ng/L组被显著诱导,而100 ng/L组在暴露25 d后被抑制.在恢复期7和20 d后,各浓度组的这些生物指标都回到与对照组相当的水平.本研究的结果表明:环境浓度水平的TBT能够引起鱼体肝脏氧化胁迫,这些生物标志物能够指示海洋环境中TBT的污染.

This study was designed to examine in vivo influence of tributyltin(TBT)at environmentally relevant concentrations on hepatic biomarkers in Sebastiscus marmoratus,which were exposed through water column to environmental concentrations of TBT(1,10,100 ng/L as Sn).Elevation of malondialdehyde(MDA)contents after exposure for 50 days indicates that TBT exposure at environmental concentrations could result in oxidative stress on liver.Glutathione peroxidase(GPx),superoxide dismutase(SOD)and catalase(CAT)activities were significantly induced by TBT after 50 days exposure.Reduced glutathione(GSH)contents in Sebastiscus marmoratus exposed to TBT for 7 days were induced and then inhibited in a dose-dependent manner for 50 days exposure.Glutathione S-transferase(GST)activities in Sebastiscus marmoratus exposed to 10 and 100 ng/L of TBT for 7 days were induced and then inhibited by TBT exposure for 25 days.These indices in all exposure groups,transferred to clean recovery tanks for 7 and 20 days,recovered to the level corresponding to that of the vehicle group.The results in the present work suggest that TBT exposure at environmental concentrations could result in oxidative stress on the fish.These biomarkers would indicate marine pollution of TBT at environmental concentrations.