LAS、Cd^(2+)复合污染对鲫鱼组织Cd蓄积及抗氧化酶活性的影响

Effects of combined toxicity of LAS and Cd^(2+) on Cd accumulation and antioxidant enzyme activities in Carassius auratus

采用暴露试验法,研究十二烷基苯磺酸钠(LAS)与重金属Cd2+单独及复合污染对鲫鱼鳃、肝脏、肌肉等部位的Cd蓄积及其超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性的影响.结果表明:单一Cd2+处理时,随着Cd2+浓度增加,鲫鱼鳃、肝脏、肌肉3部位的Cd蓄积量均极显著增加(P<0.01),各组织蓄积量顺序为:肝脏>鳃>肌肉;在LAS与Cd2+复合处理条件下,Cd在这3组织中的分布仍符合以上规律,但鲫鱼各组织对Cd的蓄积量发生改变,其中0.4 mg·L-1Cd2+与5.0 mg·L-1LAS复合处理能极显著促进鲫鱼肝脏对Cd的蓄积(P<0.01);2.0 mg·L-1Cd2+与不同浓度的LAS复合处理均能极显著促进鲫鱼肝脏、肌肉对Cd的蓄积(P<0.01);另外,2.0 mg·L-1Cd2+与5.0 mg·L-1LAS复合处理能极显著促进鲫鱼鳃对Cd的蓄积(P<0.01);其余各复合组与相应单一Cd2+处理组间无显著差异;LAS与Cd2+单一及复合处理对鲫鱼鳃、肝脏、肌肉的SOD、CAT活性均有明显影响,其中鲫鱼肝脏SOD活性变化能更灵敏地反映污染物对鲫鱼的毒性程度.

To investigate the combined toxic effects of linear alkylbenzene sulphonates （LAS） and Cd^2＋ in Carassiusauratus, Cd accumulations and the activities of superoxide dismutase （SOD） and catalase （CAT） were measured in gill, liver and muscles of C. auratus by exposure to single or combinations of LAS and Cd^2＋. The results indicated that single Cd^2＋ exposure induced its accumulation in all these three tissues with the sequence of liver 〉 gill〉 muscles. Meanwhile, the combined effects of Cd^2＋ and LAS exhibited a similar pattern in Cd accumulation compared with the single Cd^2＋ exposure in the three tissues. The combination of 0. 4 mg·L^-1 ^2＋ and 5.0 mg·L^-1 LAS induced higher Cd concentration in liver; the combination of 2.0mg·L^-1 Cd^2＋ and all the levels of LAS induced higher Cd concentration in liver and muscles; and the combination of 2.0 mg·L^-1 Cd^2＋ and 5.0mg·L^-1 LAS increased higher Cd concentration in gill, as compared with the control. Single or combinations of Cd^2＋ and LAS all influenced the activities of SOD and CAT in three tissues of C. auratus. The changes of SOD activity in liver can reflect better the toxic degree of pollutants to C. auratus.