Miwa K, Igawa A, Nakagawa K, Hirai T, Inoue H
Department of Internal Medicine, Toyama Medical and Pharmaceutical University, Japan.
Cardiovasc Res. 1999 Jan;41(1):291-8. doi: 10.1016/s0008-6363(98)00207-7.
The plasma status of vitamin E has been suggested to be linked to the activity of coronary artery spasm. This study was designed to determine whether vitamin E is actually consumed in the coronary circulation in patients with active variant angina having repetitive spasm-induced transient myocardial ischemia and reperfusion.
Blood samples were obtained simultaneously from the aortic root, coronary sinus and right atrium in 12 patients with variant angina due to spasm of the left coronary artery, nine patients with stable effort angina and nine control subjects. Plasma vitamin E (alpha- and gamma-tocopherol) concentrations were determined by use of high-performance liquid chromatography and plasma lipid peroxides were measured as thiobarbituric acid-reactive substances (TBARS).
At baseline, both plasma alpha- (p < 0.01) and gamma- (p < 0.05) tocopherol levels were significantly lower in the coronary sinus (5.50 +/- 0.50 and 0.55 +/- 0.07 mg/l, mean +/- SEM) than in the aortic root (6.63 +/- 0.57 and 0.63 +/- 0.08 mg/l) and also in the right atrium (6.44 +/- 0.61 and 0.63 +/- 0.09 mg/l) in the variant angina group. The TBARS level was significantly (p < 0.05) higher in the coronary sinus than in the aortic in this group. In contrast, these levels were not significantly different between the samples from the coronary sinus and the aortic root or the right atrium in the control group and also in the stable effort angina group. The coronary sinus-aortic difference in plasma vitamin E levels in the variant angina group was not significantly altered after left coronary artery spasm induced by intracoronary injection of acetylcholine. Also, the plasma vitamin E levels in the aortic root, coronary sinus and right atrium all remained unchanged in the stable effort angina group after pacing-induced angina and in the control group after intracoronary administration of acetylcholine.
Transcardiac reduction in plasma vitamin E concentrations concomitant with lipid peroxide formation was demonstrated in patients with active variant angina, suggesting actual consumption of this major endogenous antioxidant. Oxidative stress and vitamin E exhaustion may be involved in the pathogenesis of coronary artery spasm.
有人提出维生素E的血浆状态与冠状动脉痉挛的活动有关。本研究旨在确定在患有重复性痉挛诱导的短暂性心肌缺血和再灌注的活动性变异型心绞痛患者中，维生素E是否真的在冠状动脉循环中被消耗。
从12例因左冠状动脉痉挛导致变异型心绞痛的患者、9例稳定劳力型心绞痛患者和9例对照者的主动脉根部、冠状窦和右心房同时采集血样。采用高效液相色谱法测定血浆维生素E（α-和γ-生育酚）浓度，并以硫代巴比妥酸反应物质（TBARS）测定血浆脂质过氧化物。
基线时，变异型心绞痛组冠状窦的血浆α-生育酚（p < 0.01）和γ-生育酚（p < 0.05）水平（分别为5.50±0.50和0.55±0.07mg/L，均值±标准误）显著低于主动脉根部（分别为6.63±0.57和0.63±0.08mg/L）和右心房（分别为6.44±0.61和0.63±0.09mg/L）。该组冠状窦的TBARS水平显著高于主动脉（p < 0.05）。相比之下，对照组和稳定劳力型心绞痛组冠状窦与主动脉根部或右心房样本之间的这些水平无显著差异。冠状动脉内注射乙酰胆碱诱导左冠状动脉痉挛后，变异型心绞痛组血浆维生素E水平的冠状窦-主动脉差异无显著改变。同样，稳定劳力型心绞痛组起搏诱导心绞痛后以及对照组冠状动脉内给予乙酰胆碱后，主动脉根部、冠状窦和右心房的血浆维生素E水平均保持不变。
在活动性变异型心绞痛患者中，证实了血浆维生素E浓度经心脏降低并伴有脂质过氧化物形成，提示这种主要内源性抗氧化剂被实际消耗。氧化应激和维生素E耗竭可能参与冠状动脉痉挛发病机制。
