Abstract: In order to study the toxic effects of diethyl phthalate (DEP) on fish for biomarkers, the carps ([WTBX]Cyprinus carpio[WTBZ] Linnaeus) were exposed to 0.125(T1), 0.5(T2), 2.0(T3) and 8.0(T4) mg·L^-1 of DEP for 2 and 20 days, respectively, with water and tween-80 as controls. The effects of DEP on antioxidant defense system and injury indicators in kidney and energy metabolism enzymes in gill were carried out. And the tissue structures of kidney and gill were observed through conventional histological sections and HE staining techniques. The results indicated that there were no obvious differences of anti-hydroxyl radical ability and MDA content in DEP treatment groups compared with the control groups when exposed for 2 days. However, GSH-PX activities and anti-superoxide anion radical ability at each treatment group and SOD activities at T3 and T4 groups and CAT activities at T1 group increased significantly. CAT activities at T3 and T4 groups decreased markedly. Meanwhile, there were no obvious changes in MAO activities of kidney at each treatment group. But activities of ATPase in gill of each DEP treatment group and LDH in gill at T2, T3 and T4 groups and contents of CRE in serum at T3 and T4 increased significantly. When exposed for 20 days, anti-superoxide anion radical ability at T2 and T3 DEP groups, SOD and GSH-PX activities at T1 and MDA contents at T2, T3 and T4 groups increased significantly. CAT activities at every treatment group, anti-hydroxyl radical ability at T3 and T4, anti-superoxide anion radical ability and GSH-PX and SOD activities at T4 were inhibited remarkably. The results also show that,, there were no significant differences in ATPase activities in gill at all treatment groups. However, LDH activities in gill at each DEP treatment group and CRE contents in serum at T2, T3 and T4 groups increased significantly, and MAO activity in kidney at T3 and T4 decreased obviously. At the same time, the gill at T4 group and the kidney at T3 and T4 groups were damaged. This study could provide a theoretic evidence for the evaluation of ecological risk to water environments and biomarkers of DEP.

Key words: diethyl phthalate(DEP), Cyprinus carpio Linnaeus, antioxidant defense system, renal injury indicator, gill energy metabolism enzyme, tissue structure

摘要： 为了探讨邻苯二甲酸二乙酯(DEP)对鱼类的毒性影响,寻找生物标志物,以水和吐温80为对照,用浓度为0.125(T1)、0.5(T2)、2.0(T3)、8.0(T4) mg·L^-1的DEP分别对鲤鱼暴露2 d和20 d,研究DEP对鲤鱼肾脏抗氧化防御系统、肾损伤指标和鳃能量代谢酶的影响,并利用常规组织切片和HE染色技术观察鳃、肾组织的结构变化。结果表明,与水和吐温80组相比,暴露2 d时,各DEP组的抗羟自由基能力,丙二醛(MDA)含量均无显著变化,但抗超氧阴离子自由基能力、谷胱甘肽过氧化物酶(GSH-PX)活力及T3、T4的超氧化物歧化酶(SOD)活力,T1的过氧化氢酶(CAT)活力均显著升高,T3、T4的CAT活力却显著降低;各DEP组的肾单胺氧化酶(MAO)活力无显著变化,而鳃腺苷三磷酸酶(ATPase)及T2、T3、T4的鳃乳酸脱氢酶(LDH)活力,T3、T4的血清肌酐(CRE)含量均显著升高。暴露20 d时,T2、T3的抗超氧阴离子自由基能力,T1的SOD、GSH-PX活力及T2、T3、T4的MDA含量均显著升高,各DEP组CAT活力,T3、T4的抗羟自由基能力,T4的抗超氧阴离子自由基能力及GSH-PX、SOD活力均明显受到抑制;各DEP组鳃ATPase活力无显著变化,但鳃LDH活力及T2、T3、T4的血清CRE含量显著升高,T3、T4的肾MAO活力显著降低;组织学观察表明, 此时T4的鳃,T3、T4的肾均发生了组织结构损伤。本研究为科学评价DEP的水环境生态风险、寻找生物标志物提供了科学依据。

关键词: 邻苯二甲酸二乙酯, 鲤鱼, 抗氧化防御系统, 肾损伤指标, 鳃能量代谢酶, 组织结构