中文摘要：

在pH值为6.0、6.5、6.8、7.5、8.0、8.5条件下,对背角无齿蚌（Anodonta woodiana）血清超氧化物歧化酶（SOD）,肝过氧化氢酶（CAT）,血清碱性磷酸酶（AKP）,血清酸性磷酸酶（ACP）活性及肝丙二醛（MDA）含量的变化进行了测定。结果发现蚌体内SOD、CAT、ACP和AKP活性在pH8.5时均低于对照组 而当pH高于对照组（pH6.8）时,MDA含量随pH升高而逐渐上升。当pH低于对照组时,MDA含量随着pH降低也逐渐上升 除ACP活性在pH6.5时略有上升外 SOD、CAT、ACP和AKP活性在pH6.0时均低于对照。SOD活性仅在pH7.5时与对照组之间没有显著差异（P〉0.05） CAT活性仅在pH8.5时存在显著差异（P〈0.05） ACP活性在pH8.0和8.5时均有显著差异（P〈0.05） 而AKP活性在pH6.0时存在极显著的差异（P〈0.01）,在pH8.5和pH7.5与对照组之间均为显著差异（P〈0.05）。MDA含量在pH6.0和pH8.5时与对照组间均存在显著差异（P〈0.05）。

英文摘要：

This paper measured on the changes of the activities of Superoxide dismutase （SOD）, Catalase （CAT）, Acid phosphatase （ACP） ,Alkaline phosphatase （AKP） and the content of Malodialdehyde （MDA） of Anodonta woodiana under different pH （6.0,6.5 ,6.8,7.5,8.0,8.5 ） condition. The results indicated that when the pH were higher than the control group （ pH 6.8 ）, the activities of SOD, CAT, ACP and AKP in Anodonta woodiana all lower than the control group at pH 8.5 ; but the content of MDA went up with the increase of pH ; When the pH were lower than the control, the content of MDA also went up with the decrease of pH;Except the activity of ACP in- creased a little at pH 6.5, the activities of SOD, CAT, ACP and AKP all lower than the control at pH 6.0. The activ- ity of SOD only at pH 7.5 have no significant difference compared with the control group （ P 〉 0.05 ） ; but the activ- ity of CAT only at pH 8.5 exists significant difference （ P 〈 0.05 ）. The activity of ACP at pH 8.0 and pH 8.5 all have significant difference （ P 〈 0.05 ）. But the activity of AKP exists statistically significant difference （ P 〈 0.01 ） at pH 6.0 and significant difference at pH 8.5 and pH 7.5 （ P 〈 0.05 ）. The content of MDA have significant difference at pH 6.0 and pH 8.5 （ P 〈 0.05 ）.