Jackson C V, Mickelson J K, Stringer K, Rao P S, Lucchesi B R
J Pharmacol Methods. 1986 Jul;15(4):305-20. doi: 10.1016/0160-5402(86)90010-0.
Oxygen-derived free radicals and other oxidizing species are thought to be involved in inflammation and ischemic tissue injuries. Recently, oxygen-derived free radicals also have been implicated in tissue injury of the myocardium subjected to ischemia/reperfusion. The purpose of this investigation was to determine if electrolysis of a physiological buffer would serve as a source of free radicals, and if these radicals would lead to alterations in myocardial function. Isolated Langendorff-perfused rabbit hearts perfused with buffer subjected to a 20 mA D.C. current for 2 min demonstrated significant increases in coronary perfusion pressure (37 +/- 6 mmHg), left ventricular end diastolic pressure (41 +/- 7 mmHg), and loss in left ventricular developed pressure (35 +/- 5%). The free radical scavengers, superoxide dismutase and a combination of tryptophan plus glycine, were effective in protecting the hearts from the effects of electrolysis. The presence of free radicals was semiquantitated with a radical-luminol chemiluminescent assay. In this assay a variety of radical scavengers and antioxidants were effective (i.e., dimethyl sulfoxide, nitro blue tetrazolium, ascorbate, superoxide dismutase, 1, 3-diphenylisobenzofuran, and glycine, catalase), whereas mannitol and tryptophan were not effective. The data indicate that electrolysis of a physiological buffer produces a milieu containing several reactive oxygen species or free radicals that have the potential to produce alterations in a biological system. This method has the advantage over existing protocols for the generation of radicals in that it is a blood-free and an enzyme-free system.
氧衍生的自由基和其他氧化物质被认为与炎症和缺血性组织损伤有关。最近，氧衍生的自由基也被认为与经历缺血/再灌注的心肌组织损伤有关。本研究的目的是确定生理缓冲液的电解是否会作为自由基的来源，以及这些自由基是否会导致心肌功能的改变。用20毫安直流电对灌注缓冲液的离体Langendorff灌流兔心进行2分钟的电解，结果显示冠状动脉灌注压显著升高（37±6毫米汞柱），左心室舒张末期压力显著升高（41±7毫米汞柱），左心室发育压力损失显著（35±5%）。自由基清除剂、超氧化物歧化酶以及色氨酸加甘氨酸的组合能有效保护心脏免受电解的影响。自由基的存在通过自由基-鲁米诺化学发光测定法进行半定量。在该测定中，多种自由基清除剂和抗氧化剂是有效的（即二甲基亚砜、硝基蓝四唑、抗坏血酸、超氧化物歧化酶、1,3-二苯基异苯并呋喃和甘氨酸、过氧化氢酶），而甘露醇和色氨酸则无效。数据表明，生理缓冲液的电解产生了一个含有多种活性氧物种或自由基的环境，这些物质有可能在生物系统中产生改变。该方法相对于现有的自由基生成方案具有优势，因为它是一个无血且无酶的系统。
