镉和汞对中华圆田螺超氧化物歧化酶活性的影响

Effect of Cadmium and Mercury on Superoxidedismutase Activity of the Mudsnail(Cipangopaludina cahayensis)

采用急性毒性试验方法,研究了不同质量浓度的镉离子(Cd2+)和汞离子(Hg2+)染毒对田螺肝胰脏超氧化物歧化酶(SOD)活性的影响.结果表明:低浓度的Cd2+、Hg2+溶液对田螺肝胰脏SOD活性具有抑制—诱导—抑制作用;高浓度的Cd2+、Hg2+溶液有抑制作用,抑制作用随着时间的延长和浓度的增大而增强.可以通过检测中华圆田螺SOD活性的变化,来直接评价环境中重金属污染对生物的毒性效应.

The activity of SOD from Cipangopaludirta cahayensis under different concentrations of Cd^2＋ and/or Hg^2＋ was investiga- ted using the acute exposure assay. The results showed that, under low concentration of Cd^2＋ or Hg^2＋ , the activity of SOD was inhibi- ted first, and then indueed with the concentration increase of the metal ions, further increase of the metal ion concentrations could re- sult in the inhibition of SOD activity again. At high concentrations of the Cd^2＋ or Hg^2＋ , the activity of SOD was inhibited, and the in- hihiiton was proportional to the exposure time and concentration of the metal ions. This study demostrated that the toxicity of the heavy metal to the biologies could be directly evaluated by monitoring the activity of SOD from Cipangopaludina cahayensis.