Kitagawa Hirotoshi, Yamazaki Toji, Akiyama Tsuyoshi, Sugimachi Masaru, Sunagawa Kenji, Mori Hidezo
Department Anesthesiology, Shiga University of Medical Science, Otsu, Japan.
Am J Physiol Heart Circ Physiol. 2005 Aug;289(2):H924-30. doi: 10.1152/ajpheart.01207.2004. Epub 2005 Apr 15.
Direct monitoring of myoglobin efflux during ischemia and reperfusion has been limited because of inherent sample collection problems in the ischemic region. Recently, the cardiac dialysis technique has offered a powerful method for monitoring myocardial interstitial levels of low-molecular-weight compounds in the cardiac ischemic region. In the present study, we extended the molecular target to high-molecular-weight compounds by use of microdialysis probes with a high-molecular-mass cutoff and monitored myocardial interstitial myoglobin levels. A dialysis probe was implanted in the left ventricular free wall in anesthetized rabbits. The main coronary artery was occluded for 60 or 120 min. We examined the effects of myocardial ischemia and reperfusion on myocardial interstitial myoglobin levels. Interstitial myoglobin increased within 15 min of ischemia and continued to increase during 120 min of ischemia, whereas blood myoglobin increased at 45 min of ischemia. Lactate and myoglobin in the interstitial space increased during the same period. At 60 min of ischemia, reperfusion markedly accelerated interstitial myoglobin release. The interstitial myoglobin level was fivefold higher at 0-15 min of reperfusion than at 60-75 min of coronary occlusion. The dialysis technique permits earlier detection of myoglobin release and separately monitors myoglobin release during ischemia and reperfusion. Myocardial interstitial myoglobin levels can serve as an index of myocardial injury evoked by ischemia or reperfusion.
由于缺血区域存在固有的样本采集问题，缺血和再灌注期间对肌红蛋白流出的直接监测一直受到限制。最近，心脏透析技术为监测心脏缺血区域低分子量化合物的心肌间质水平提供了一种强大的方法。在本研究中，我们通过使用具有高分子量截留值的微透析探针，将分子靶点扩展到高分子量化合物，并监测心肌间质肌红蛋白水平。将透析探针植入麻醉兔的左心室游离壁。主冠状动脉闭塞60或120分钟。我们研究了心肌缺血和再灌注对心肌间质肌红蛋白水平的影响。间质肌红蛋白在缺血15分钟内增加，并在120分钟的缺血期间持续增加，而血肌红蛋白在缺血45分钟时增加。同期间质中的乳酸和肌红蛋白增加。在缺血60分钟时，再灌注显著加速了间质肌红蛋白的释放。再灌注0 - 15分钟时的间质肌红蛋白水平比冠状动脉闭塞60 - 75分钟时高五倍。透析技术能够更早地检测到肌红蛋白的释放，并分别监测缺血和再灌注期间的肌红蛋白释放。心肌间质肌红蛋白水平可作为缺血或再灌注诱发心肌损伤的指标。
