全氟辛烷磺酸钾对真鲷谷胱甘肽质量分数和谷胱甘肽转硫酶活性的影响

为了解全氟辛烷磺酸钾（PFOS）对海洋鱼类抗氧化防御系统的毒性效应及致毒机理,在实验室条件下研究了PFOS胁迫和净水恢复过程中真鲷（Pagrosomus major）鳃组织和肝脏组织内谷胱甘肽（GSH）质量分数与谷胱甘肽转硫酶（GST）活性的变化。结果显示,胁迫开始时鳃中w（GSH）在低浓度组出现诱导,中、高浓度组出现抑制现象,随着胁迫时间的延长,各浓度组处于显著诱导水平（P〈0.01）;肝脏中w（GSH）在胁迫第15天时各浓度组中出现显著的剂量效应,w（GSH）随着PFOS曝露浓度的升高而降低。真鲷2种组织的GST活性变化与各自组织中w（GSH）的变化趋势相近。净水恢复期内个别浓度组的指标恢复到对照组水平,说明真鲷可以修复PFOS胁迫造成的损伤。结果表明,PFOS在试验条件下对真鲷有显著的毒性作用,可能对海洋高等生物存在潜在性危害,应对其海洋环境风险评价加以关注。

Effect of perfluorooctane sulfonate potassium on glutathione content and glutathione S-transferase activity of red sea bream

To understand the toxic effect and mechanism of perfluorooctane sulfonate potassium（PFOS） on antioxidant defense system of marine fish,we studied the changes of GSH content and GST activity in gill and liver of red sea bream（Pagrosomus major） during PFOS stress and water purifying under laboratory conditions.The results show that at the beginning of exposure,GSH content in gill was induced at low concentration but inhibited at middle and high concentration;GSH content was significant inducted（P〈0.01） with time,and on 15th day of stress,GSH content had significant dose effect at various concentrations;GSH content was reduced with increasing PFOS exposure concentration.The change of GST activity was similar with GSH content in gill and liver.The biomarkers in some groups recovered to the level in the control during water purifying,which suggests red sea bream can repair damage caused by PFOS stress.Therefore,PFOS has obvious toxic effects on red sea bream under laboratory conditions,and may be harm to marine higher organisms.Risk assessment of marine environment should be concerned about.