苯并（a）芘对大弹涂鱼肝脏超氧化物歧化酶活性的影响

在实验生态条件下，研究了在苯并（a)芘（BaP)胁迫下大弹涂鱼肝脏超氧化物歧化酶（SOD）活性的变化，结果显示：暴露3d时，不同BaP含量组大弹涂鱼肝脏SOD活性无显著差异（P＞0．05），而暴露7d时，随着B aP含量的升高，0.5mg/dm^3 BaP含量组SOD活性被显著诱导（P＜0．05），为对照组的1．87倍；随着暴露时间的延长，各含量组肝脏SOD的活性均表现出不同程度的下降趋势，其中对照组肝脏SOD活性显著降低，表明SOD活性易受污染以外的因素，如水体容量、铒料、光照等的影响。污染解除后，0.5mg/dm^3含量组SOD活性显著升高，表明大弹涂鱼肝脏仍具有较强的生理调节机能，也可能表明SOD活性的变化相对于环境因子改变的“迟滞性”。以上这些结果表明SOD有可能作为大弹涂鱼受BaP胁迫的生物指标。

Effects of benzo(a)pyrene on superoxide dismutase activity

Changes of superoxide dismutase(SOD) activities in liver of Boleophthalmus pectinirostris with benzo(a)pyrene(BaP) exposure were detected in experimental condition. The results show that there is no greatly changes for SOD activities at different concentrations in 3d exposure( P >0.05), whereas it is induced significantly with the increase of concentrations in 7d exposure( P <0.05,1.87 times of control for SOD activities at BaP concentration of 0.5 mg/dm 3 ). With the prolonged exposure, SOD activities at different concentrations decrease to some extent. SOD activities in control group decrease significantly, which shows that factors other than contaminants , such as volume, diet and light have effect on SOD activities. The activities of SOD increase significantly after BaP was removed. It turned out that the physiological modulatary mechanism is still existed in liver of Boleophthalmus pectinirostris . All of the results show that SOD activity might be suitable to be the bioindicator of BaP exposure.