苯并(a)芘对大弹涂鱼肝脏谷胱甘肽过氧化物酶活性的影响

Effects of benzo(a)pyrene exposure on glutathione peroxidase activity in the liver of Boleophthalmus pectinirostris

研究大弹涂鱼 (Boleophthalmuspectinirostris)暴露于 0 .0 5、0 .2 0和 0 .50mg/L不同质量浓度苯并(a)芘 (BaP)溶液中 1周 ,其肝脏谷胱甘肽过氧化物酶 (GPx)活性的变化。结果显示 ,0 .5mg/LBaP组中 ,随暴露时间的延长 ,大弹涂鱼肝脏GPx活性被显著抑制 (P≤ 0 .0 5) ;暴露 3d ,随BaP浓度的增加 ,GPx活性显著降低 (P≤ 0 .0 5) ,表明高剂量的BaP可对其肝脏产生毒性作用。将大弹涂鱼暴露于 0 .50mg/LBaP 3d ,再转入清洁海水中 4d ,其肝脏GPx活性可恢复至对照组水平 ,表明其肝脏仍具有较强的生理调节机能。GPx活性的变化间接反映了环境中氧化污染物的存在 ,有可能作为大弹涂鱼受BaP胁迫的生化指标。

Boleophthalmus pectinirostris were exposed to BaP containing seawater at concentrations of 0.05, 0.20 and 0.50 mg/L for 1 week. The analysis results showed that the glutathione peroxidase (GPx) activities in the liver of B. pectinirostris decreased significantly with prolonged BaP exposure time at concentration of 0.50 mg/L (P≤0.05). During 3 days exposure, the GPx activities decreased significantly with the increasing of BaP concentration (P≤0.05). It is supposed that exposure to higher concentration of BaP may produce toxic effect on the liver. The GPx activity recovered the same level as control after 3 days BaP exposure at concentration of 0.50 mg/L and 4 days recovery in clear seawater. It turns out that the physiological modulatary mechanism does work in the liver of B.pectinirostris. It can be concluded that the changes of GPx activity can reflect the existence of redox reactive contaminants in the environment so that GPx activity can be a bio chemical indicator of BaP exposure for B.pectinirostris.