Department of Pathophysiology, Victor Babeş University of Medicine and Pharmacy, Timişoara, Romania.
Mol Cell Biochem. 2013 Jul;379(1-2):229-34. doi: 10.1007/s11010-013-1644-4. Epub 2013 Apr 9.
High-resolution respirometry of permeabilized myocardial fibers offers reliable insights concerning the integrated mitochondrial function while using small amounts of cardiac tissue. The aim of the present study was to assess the respiratory function in permeabilized fibers of human right atrial appendages harvested from patients with coronary heart disease (CHD) (n = 6) versus patients with valvular disease (n = 5) and preserved ejection fraction that underwent non-emergency cardiac surgery. Human bundle samples (1-3 mg wet weight) permeabilized with saponin were transferred into the 2 ml Oxygraph-2 k chambers to measure complex I(CI) and II (CII)-dependent respiration, respectively. The following values (expressed in pmol/s mg) were obtained for CI-dependent respiration: oxidative phosphorylation (OXPHOS), 35.65 ± 1.10 versus 42.43 ± 1.08, electron transport system (ETS), 37.87 ± 1.72 versus. 46.58 ± 1.85, and respiratory control ratio (RCR, calculated as the ratio between OXPHOS and LEAK states), 2.43 ± 0.09 versus 2.73 ± 0.068 (p < 0.05). In conclusion, in patients with CHD we showed a significant decline for the OXPHOS capacity, ETS and RCR for mitochondria energized with CI (but not with CII) substrates. These observations are suggestive for an early impairment of complex I supported respiration in ischemic heart disease, as previously demonstrated in the setting of experimental ischemia/reperfusion in several animal species.
经皂素处理的心肌纤维通透性的高分辨率呼吸测定法，在使用少量心脏组织的情况下，可提供有关整合线粒体功能的可靠信息。本研究旨在评估取自冠心病（CHD）（n = 6）与瓣膜病患者（n = 5）的右心耳心肌纤维通透性的呼吸功能，这些患者射血分数正常且接受了非紧急心脏手术。将用皂素处理的人束样本（1-3 毫克湿重）转移到 2 ml Oxygraph-2 k 室中，分别测量复合物 I（CI）和 II（CII）依赖性呼吸。获得的以下值（以 pmol/s mg 表示）用于 CI 依赖性呼吸：氧化磷酸化（OXPHOS），35.65 ± 1.10 与 42.43 ± 1.08，电子传递系统（ETS），37.87 ± 1.72 与 46.58 ± 1.85，呼吸控制比（RCR，计算为 OXPHOS 与 LEAK 状态之间的比值），2.43 ± 0.09 与 2.73 ± 0.068（p < 0.05）。总之，在 CHD 患者中，我们发现，与 CI（而非 CII）底物供能的线粒体的 OXPHOS 能力、ETS 和 RCR 显著下降。这些观察结果表明，在缺血性心脏病中，复合物 I 支持的呼吸出现了早期损伤，正如在几种动物物种的实验性缺血/再灌注模型中所证明的那样。
