【摘要】 以α- 苯基- N -叔丁基甲亚胺- N -氧化物(α- phenyl- N -tert butylnitrone ,PBN)为自旋捕获剂,利用电子顺磁共振(electronparamagneticresonance ,EPR)研究了- 2 ,4 - 二氯苯酚(2 ,4 - dichlorophenol,2 ,4 - DCP)腹腔注射2 4h后,引起鲫鱼(Carassiusauratus)幼体肝脏内自由基含量变化.结果表明,不同剂量2 ,4 - DCP(0 . 0 2 5 ,0 . 0 5 ,0 . 5 ,5 ,2 5mg/kg)腹腔注射2 4h后可引起鲫鱼肝脏内自由基信号明显增强,与对照组相比具有显著性差异(p <0 . 0 5 ) .自由基的产生与2 ,4 DCP注射剂量呈较好的剂量效应关系,回归方程为:y =1 1. 89ln(x) +92. 2 0 ,r2 =0 . 985 6 .EPR波谱的3组双重峰分裂谱线为典型的PBN捕获羟自由基形成PBN/ ·OH的EPR波谱,经谱图解析表明,PBN捕获自由基形成加合物的超精细分裂常数aN =1 3 . 7Gauss,aH =1 . 8Gauss ,g因子为2 . 0 0 5 8.与文献报道的PBN捕获羟自由基的特征参数一致.研究发现,2 ,4 - DCP腹腔注射引起鲫鱼肝脏丙二醛(malondialdehyde ,MDA)含量明显增加,与对照组相比有显著性差异(p <0 . 0 5 ) ,并对2 ,4 - DCP诱导鲫鱼肝脏自由基的产生与脂质过氧化的机理进行了探讨.更多还原

【Abstract】 Free radical generation in liver of larval fish(Carassius auratus) after 2,4-dichlorophenol(2,4-DCP) injected intraperitoneally 24h was studied with electron paramagnetic resonance(EPR) spin trapping technique and α-phenyl-N-tert-butylnitrone(PBN) as spin trap reagent. The results show that there is a significant increase of free radical generation in the liver of the fish treated with 2,4-DCP(0.025, 0.05, 0.5, 5, 25 mg/kg) compared with that of the control(p<0.05). The free radical generation correlates well with the dose of 2,4-DCP administered. The regress equation for dose-effect relation is y=1189ln(x)+9220,r2=0.9856. The six-line composed of three groups with two hyperfine splitting peaks in each shows a typical PBN/ ·OH EPR spectrum. The hyperfine splitting constants for the PBN-adducts is aN=13.7 Gauss, aH=1.8 Gauss, g factor is 2.0058, which is consistent with the characteristics of PBN-hydroxyl radical adduct reported from the literature. Results also show that there is a significant increase for malondialdehyde(MDA) content in the treated groups compared with that of the control(p<0.05). The mechanisms of free radical generation and lipid peroxidation induced by 2,4-DCP are discussed in this study.更多还原