Klegeris A, Korkina L G, Greenfield S A
University Department of Pharmacology, Oxford, UK.
Free Radic Biol Med. 1995 Feb;18(2):215-22. doi: 10.1016/0891-5849(94)00141-6.
Oxidation products of catecholamines, particularly dopamine, could play an important role in the physiology and pathology of the nervous system. This study has therefore characterised autoxidation of dopamine monitored in a variety of systems. Lucigenin-dependent chemiluminescence and reduction of cytochrome c were exploited to register generation of the byproduct superoxide anion, whereas the quinone product was detected by a direct spectrophotometric measurement. Accumulation of hydrogen peroxide was followed as an increase in luminol-dependent chemiluminescence. In all cases, basic solutions were used to initiate the oxidation of dopamine. The results obtained could be interpreted as specific reactions at the particular stages of the autoxidation process: the luminol-dependent chemiluminescence system detected accumulation of hydrogen peroxide during dopamine oxidation, whereas the lucigenin-dependent chemiluminescence indicated generation of superoxide anion. Furthermore, cytochrome c reduction, observed during dopamine oxidation, was probably attributed to a direct interaction with dopamine semiquinone. In addition, the effects of superoxide dismutase, catalase, and peroxidase were examined in each of the systems: Each enzyme exhibited a different effect in each system used. The possible reaction mechanisms leading to different action of enzymes affecting reactive oxygen species are discussed. The methods described here of monitoring dopamine autoxidation could thus be used in parallel to detect the effects of different preparations on various stages of the dopamine autoxidation process.
儿茶酚胺的氧化产物，尤其是多巴胺的氧化产物，可能在神经系统的生理和病理过程中发挥重要作用。因此，本研究对在多种体系中监测到的多巴胺自氧化进行了表征。利用光泽精依赖性化学发光和细胞色素c的还原反应来记录副产物超氧阴离子的生成，而醌产物则通过直接分光光度法进行检测。过氧化氢的积累通过鲁米诺依赖性化学发光的增加来跟踪。在所有情况下，均使用碱性溶液引发多巴胺的氧化反应。所获得的结果可解释为自氧化过程特定阶段的特异性反应：鲁米诺依赖性化学发光体系检测到多巴胺氧化过程中过氧化氢的积累，而光泽精依赖性化学发光表明超氧阴离子的生成。此外，多巴胺氧化过程中观察到的细胞色素c还原可能归因于其与多巴胺半醌的直接相互作用。另外，在每个体系中都检测了超氧化物歧化酶、过氧化氢酶和过氧化物酶的作用：每种酶在所用的每个体系中都表现出不同的作用。本文讨论了导致影响活性氧的酶产生不同作用的可能反应机制。因此，这里描述的监测多巴胺自氧化的方法可同时用于检测不同制剂对多巴胺自氧化过程各个阶段的影响。
