我国近岸局部海域的重金属污染严重威胁着生态环境和人类健康。吡啶硫酮铜(CuPT)和吡啶硫酮锌(ZnPT)在海洋防污和化工产品中的应用近来逐年增加,对其生态毒性及其机理进行研究迫在眉睫。本文以我国南海常见多毛类——华美盘管虫(Hydroides elegans Haswell)为受试生物,研究了CuPT和ZnPT对华美盘管虫的抗氧化系统的影响。试验结果表明在CuPT和ZnPT胁迫下,华美盘管虫体内的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和谷胱甘肽还原酶(GR)的活性,以及还原型谷胱甘肽含量(GSH)和丙二醛(MDA)含量发生与暴露毒物种类、浓度和时间相关的变化。SOD、CAT和GR的活性在较低浓度(25μg·L^-1)的CuPT胁迫6 h后呈显著上升趋势,但随暴露时间延长(12 h和24 h),GR的活性显著下降;而暴露于较低浓度(50μg·L^-1)的Zn PT中,仅SOD活性显著升高,CAT和GR的活性都显著下降。在较高Cu PT(100μg·L^-1)或Zn PT(200μg·L^-1)浓度中,CAT和GR的活性都显著下降。GSH含量对Cu PT或Zn PT胁迫的响应呈现明显的时间效应,即随暴露时间的延长,通常由显著上升转为显著下降。MDA含量在Cu PT(100μg·L^-1)或Zn PT(200μg·L^-1)高浓度组中呈显著升高趋势。
There is an increasing trend of heavy metal pollution in some offshore areas in China,which seriously threatens the local ecological environment and human health. Recently,since copper pyrithione( CuPT) and zinc pyrithione( ZnPT) are widely utilized as marine antifoulant and chemical products,it is very urgent to study the ecotoxicity of CuPT and ZnPT in marine environment. Here,Hydroides elegans,a common polychaete in the China South Sea,was used as the test animal to study the effects of CuPT and ZnPT on the antioxidant activity,including the activities of superoxide dismutase( SOD),catalase( CAT) and glutathione reductase( GR),and the contentsof reduced glutathione( GSH) and malonaldehyde( MDA). The results indicated that the activities of SOD,CAT and GR varied significantly with dose and time,when exposed to CuPT and ZnPT. The activities of SOD,CAT and GR increased significantly,when treated with low concentration of CuPT( 25 μg·L^-1) for 6 h,but the activity of GR decreased significantly when exposed for more than 12 h and 24 h. In addition,the low concentration of ZnPT( 50 μg·L^-1) increased the activity of SOD,but decreased the activities of CAT and GR. When exposed to high concentration of CuPT( 100 μg·L^-1) or Zn PT( 200 μg·L^-1),the activities of CAT and GR decreased significantly in Hydroides elegans. The content of GSH showed a time-dependent response to CuPT or ZnPT exposure,and the contents were firstly decreased and then increased with the extension of the exposure time. The content of MDA increased significantly,when exposed to high concentration of CuPT( 100 μg·L^-1) or Zn PT( 200 μg·L^-1).