【摘要】 Fenton反应是生物体内产生羟基自由基(.OH)的主要反应.Mn2+在体外可以参与类似反应生成.OH.在此基础上,本文利用自旋捕捉-ESR技术比较了Mn2+参与类Fenton反应(Fenton-like reaction)与Fe2+参与Fenton反应的能力,利用芳环羟基化(aromatic hydroxylation)反应-高效液相色谱法检测了Mn2+对Fe2+参与的Fenton反应的影响.利用电泳技术检测了上述反应产生的.OH对质粒DNA的损伤情况.结果显示,在实验条件下,Mn2+与过氧化氢(H2O2)反应产生.OH的能力仅为相同条件下Fe2+的5%左右.但Mn2+可以在Fenton反应中明显促进.OH的产生.更多还原

【Abstract】 Fenton reaction is the primary source which generates hydroxyl radical in vivo.It has been reported that manganous substitute for iron in Fenton reaction system to evolve hydroxyl radical(Fenton like reaction).In this research,electron paramagnetic resonance(ESR) spectroscopy was used to measure the intensity of hydroxyl radical which generated from Fenton reaction and Fenton like reaction.It was shown that the intensity of hydroxyl radical generated from Fenton like reaction was merely 5% compared with that from Fenton reaction at the beginning of the reaction.HPLC with fluorescence detection(excitation 277 nm and emission 306 nm) was used to detect the generation of hydroxyl radical in Fenton reaction to which micro amount of manganous was added.L-phenylalanine,which could be converted to highly fluorescent L-tyrosine in the presence of hydroxyl radical,was used as the probe.It was shown that the generation of hydroxyl radical was obviously promoted by manganous.In addition,DNA strand breaks were also used to verify above results.The results suggested that hydroxyl radical promoted by manganous in Fenton reaction might be an important reason which resulted in oxidative stress in vivo induced by manganous.更多还原