镉胁迫下钙对鲫鱼镉吸收和抗氧化酶活性的影响

Effects of Ca on Cd Uptake and Antioxidant Enzymes Activities of Crucian carp under Cd Stress

为探讨钙对镉致鲫鱼毒性效应的影响,以鲫鱼为材料,试验分5组,分别为空白对照Ⅰ组,单独染镉Ⅱ组(镉0.05mg·L^(-1)),镉钙联合组(Ⅲ组:镉0.05 mg·L^(-1)+钙40 mg·L^(-1);Ⅳ组:镉0.05 mg·L^(-1)+钙80 mg·L^(-1);Ⅴ组:镉0.05 mg·L^(-1)+钙120mg·L^(-1)),水体染毒处理35 d后,检测鲫鱼肌肉、鳃中镉质量分数,肝胰脏中T-AOC、CAT、T-SOD活性及MDA质量摩尔浓度。结果表明,染镉组和镉-钙联合组鲫鱼肉、鳃Cd^(2+)的质量分数均显著(P<0.05)高于对照组,而镉-钙联合组鲫鱼肉、鳃中Cd^(2+)的质量分数均低于单独染镉组,且鱼鳃中Ⅳ和Ⅴ组差异显著(P<0.05)。鲫鱼肝胰脏T-AOC、T-SOD和CAT活性表现为单独染镉组均显著低于(P<0.05)对照组;而镉-钙联合组其活性均高于单独染镉组,其中T-AOC、CAT活性在两个处理间的差异均达显著水平(P<0.05),T-SOD活性仅在Ⅳ和Ⅴ组间差异显著(P<0.05)。肝胰脏中MDA质量摩尔浓度表现为染镉组和镉-钙联合组均显著高于(P<0.05)对照组,而镉-钙联合组又显著低于(P<0.05)单独染镉组。由此可见,在水体中补充适量的钙剂可降低镉在鲫鱼体内的蓄积,并且对镉致鲫鱼肝胰脏抗氧化系统损伤有修复作用。

To explore the effects of calcium（Ca） on cadmium（Cd）-induced toxicity on crucian carp.We chose crucian carp and divided into five groups,i.e.,control group（GroupⅠ）,Cd alone exposed group（0.05 mg·L^-1,Group Ⅱ）,and Cd^2＋ combined with Ca^2＋ groups（Group Ⅲ：0.05 mg ·L^-1 Cd^2＋ ＋40 mg ·L^-1 Ca^2＋;Group Ⅳ：0.05 mg ·L^-1 Cd^2＋＋80 mg·L^-1 Ca^2＋;Group Ⅴ：0.05 mg ·L^-1 Cd^2＋＋120 mg ·L^-1 Ca^2＋）.After exposed for 35 days,mass fraction of Cd^2＋ in the muscle and gill and the total antioxidative capacity（T-AOC） as well as levels of total superoxide dismutase（T-SOD）,catalase（CAT） and malondialdehyde（MDA） in the hepatopancreas were assessed.The results showed that Cd levels in the muscle and gill of GroupⅡ,Group Ⅲ,Group Ⅳ and Group Ⅴ increased（P〈0.05） compared to GroupⅠ.Compared with GroupⅡ,Cd levels in the Group Ⅲ,Group Ⅳ and Group Ⅴ decreased,only in gill of Group Ⅳ and Group Ⅴ significantly（P〈0.05）.The activity of T-AOC,T-AOC and CAT in the hepatopancreas of Cd alone exposed group was lower than that in GroupⅠ（P〈0.05）,in Cd^2＋ combined with Ca^2＋ groups that was higher than that in GroupⅡ（P〈0.05）.As for MDA,its content in other four groups（Ⅱ,Ⅲ,Ⅳ and Ⅴ） was higher（P〈0.05） than that in Group I,respectively,while its level in three groups（Ⅲ,Ⅳ and Ⅴ） was lower（P〈0.05） than that in GroupⅡ,respectively.In summary,Ca can lower the accumulation of Cd in the muscle and gill of crucian carp and increase the anti-oxidative ability in the hepatopancreas,which demonstrated that Ca can alleviate the toxic effect of Cd.