盐度胁迫对黄河鲤幼鱼耐受性、肝脏抗氧化酶和鳃丝Na^(+)/K^(+)-ATPase酶活性的影响

The effects of salinity stress on tolerance,liver antioxidant activity and gill filament’s Na^(+)/K^(+)-ATPase activity of juvenile Cyprinus carpio haematoperus

为了解盐度胁迫对黄河鲤(Cyprinus carpio haematoperus)幼鱼耐受性、肝脏抗氧化酶和鳃丝Na^(+)/K^(+)-ATPase酶活性的影响,实验设置0(对照组)、3、6、9、12和15共6个盐度梯度对黄河鲤幼鱼进行盐度胁迫,在6、12、24、48、72和96 h时采样,测定肝脏中超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)和溶菌酶(LZM)的活性及丙二醛(MDA)的含量和鳃丝Na^(+)/K^(+)-ATPase酶活性。结果显示:与对照组相比,各盐度组黄河鲤幼鱼肝脏组织的SOD、CAT、LZM、GSH-Px和鳃丝Na^(+)/K^(+)-ATPase酶活性随胁迫时间的延长均有先升高后下降的趋势,且SOD、CAT、GSH-Px和鳃丝Na^(+)/K^(+)-ATPase酶活性在盐度为6时能在胁迫96 h内维持较高水平,而盐度为9、12和15时酶活性则随胁迫时间延长显著下降。各盐度组LZM酶活性在胁迫96 h内均显著高于对照组,且12和15高盐度组在胁迫96 h时仍显著高于其他组。各盐度组的MDA含量均在胁迫6 h达峰值,之后随胁迫时间延长,盐度为3、6、9组下降较显著,但12和15组的MDA含量在96 h时仍显著高于其他组。结果表明:在本试验条件下,黄河鲤幼鱼在养殖用水盐度0~6范围内适当提高盐度可提高其肝脏抗氧化性能和鳃丝Na^(+)/K^(+)-ATPase酶活力。

The present study was to evaluate the effects of salinity stress on tolerance,liver antioxidant activity and gill filament Na^(+)/K^(+)-ATPase activity of juvenile Yellow River carp.We tested acute salinity toxicity to six different salinities,0(control group),3,6,9,12 and 15.Six salinities gradients of the juvenile Yellow River carp for salinity stress,the activities of superoxide dismutase(SOD),catalase(CAT),glutathione peroxidase(GSH-px)and lysozyme(LZM),and the content of malondialdehyde(MDA)in liver,the activity of Na^(+)/K^(+)-ATPase in gill filament were determined at 6,12,24,48,72 and 96 h.The results showed that the activities of SOD,CAT,LZM,GSH-Px and Na^(+)/K^(+)-ATPase of juvenile Yellow River carp in six salinity groups were increased and then decreased with the prolongation of stress time at first.The activities of SOD,CAT,GSH-Px and gill Na^(+)/K^(+)-ATPase could keep high levels within 96 h on six salinity groups,while the enzyme activities of SOD,CAT,GSH-Px and gill Na^(+)/K^(+)-ATPase significantly decreased with the increase of stress time under 9,12 and 15 salinity group.Compared with the control group,the activity of LZM enzyme in salinity groups was significantly increased within 96 h salinity group,and 12 and 15 salinity group were still significantly higher than other groups at 96 h.MDA content in all salinity groups reached the peak at 6 h of stress,and then significantly decreased with the extension of stress time,but MDA content in groups 12 and 15 was still significantly higher than that in other groups at 96 h.In conclusion,the liver antioxidant capacity and gill Na^(+)/K^(+)-ATPase activity of juvenile yellow river carp can be improved by properly increasing the salinity in the range of 0-6 under the experimental conditions.