Coghlan J G, Flitter W D, Clutton S M, Ilsley C D, Rees A, Slater T F
Department of Cardiology, Harefield Hospital, Middlesex.
J Thorac Cardiovasc Surg. 1993 Aug;106(2):268-74.
The effects of ischemia and reperfusion on arterial and coronary sinus vitamin E and thiobarbituric acid reactive substance levels were investigated in 10 patients undergoing routine coronary artery bypass grafting. Serial sampling was performed during bypass operations, before the initial period of crossclamping and at 30 seconds and 2, 5, and 10 minutes after final crossclamp removal. A net myocardial loss of vitamin E occurred in the first 5 minutes of myocardial reperfusion (0.84 +/- 0.21 mumol/mmol cholesterol; p < 0.01). Myocardial vitamin E loss correlated positively with the total crossclamp time (rho = -0.695; p < 0.05) but was independent of cardiac enzyme release and duration of cardiopulmonary bypass. The concentration of thiobarbituric acid reactive substance rose significantly in the systemic circulation (+14 nmol/gm albumin; F > 17; p < 0.002) at 2 and 5 minutes after crossclamp removal. A significant increase of thiobarbituric acid reactive substance levels was also found in the coronary sinus blood 10 minutes after crossclamp removal (+8 nmol/gm albumin; F > 14; p < 0.004). However, there was no net arterial-coronary sinus difference in thiobarbituric acid reactive substance levels. The change in arterial thiobarbituric acid reactive substance levels in each patient was inversely correlated with their control vitamin E level (F = 9.53; p < 0.01). Our findings suggest that systemic lipid peroxidation occurs during bypass and that vitamin E may play a protective role during routine bypass grafting by attenuating the degree of peroxidative damage.
对10例行常规冠状动脉搭桥术的患者，研究了缺血及再灌注对动脉和冠状窦维生素E及硫代巴比妥酸反应性物质水平的影响。在搭桥手术期间、初次阻断前、最后一次阻断解除后30秒、2分钟、5分钟和10分钟进行系列采样。心肌再灌注的最初5分钟内出现维生素E的净心肌丢失（0.84±0.21μmol/mmol胆固醇；p<0.01）。心肌维生素E丢失与总阻断时间呈正相关（ρ=-0.695；p<0.05），但与心肌酶释放及体外循环持续时间无关。阻断解除后2分钟和5分钟时，全身循环中硫代巴比妥酸反应性物质浓度显著升高（+14nmol/g白蛋白；F>17；p<0.002）。阻断解除后10分钟，冠状窦血中硫代巴比妥酸反应性物质水平也显著升高（+8nmol/g白蛋白；F>14；p<0.004）。然而，硫代巴比妥酸反应性物质水平在动脉和冠状窦之间无净差异。每位患者动脉中硫代巴比妥酸反应性物质水平的变化与其对照维生素E水平呈负相关（F=9.53；p<0.01）。我们的研究结果表明，体外循环期间发生全身脂质过氧化，维生素E可能通过减轻过氧化损伤程度在常规搭桥术中发挥保护作用。
