中文摘要：

选择黄河上游污染程度较严重的兰州地区和相对无污染的刘家峡地区作为研究样点，比较分析了两地花背蟾蜍（Bufo raddei）肝脏和肾脏中抗氧化酶SOD、CAT和GPx活性及丙二醛（MDA）含量。与刘家峡地区相比，兰州地区花背蟾蜍肝脏的SOD活性升高，CAT和GPx活性极显著降低，肾脏GPx活性显著增高，肝脏和肾脏MDA含量明显高于刘家峡。结果表明，黄河上游环境污染使得花背蟾蜍体内氧化胁迫加重，导致其组织脂质过氧化程度升高。

英文摘要：

The activities of antioxidant enzyme SOD, CAT, GPx and the content of malondialdehyde （MDA） in liver and kidney of toad Bufo raddei sampled from two different polluted sites of the Upper Yellow River were studied. It was found that the toad from Lanzbou （polluted） had significantly descent of CAT and GPx activities in liver compared with those of Liujiaxia （relatively unpolluted） ,while the activity of SOD of the male and MDA content of the female from Lanzhou were both higher in liver than those of from Liujiaxia. There was no significant difference of the nephritic antioxidant enzyme activity except GPx depression in the female toad from Lanzhou as well as the increased MDA content in kidney. It was suggested that the environmental pollution in the Upper Yellow River induced oxidative stress and increase of lipid peroxidation on Bufo raddei.