ISCHEMIC MYOCARDIAL MITOCHONDRIAL FUNCTION AND ULTRASTRUCTURAL CHANGE : Influence of Regional Myocardial Blood Flow

• Published in: JAPANESE CIRCULATION JOURNAL Vol. 55; no. 7; pp. 714 - 720
• Main Authors: MIYAZIMA, KAZUYUKI, MATSUBARA, TATSUAKI, NAKAO, MASAHIDE, IYEDA, NOBUTO, NISHIDA, TOMOATSU, OKAMOTO, YOSHIHITO, ITOH, KEN-ICHI, KAMBE, TADASHI, NAKAMURA, SHIGEO, SAKAMOTO, NOBUO
• Format: Journal Article
• Language: English
• Published: Kyoto The Japanese Circulation Society 1991; Japanese Circulation Society
• Subjects: Adenosine Triphosphate - analysis; Animals; Biological and medical sciences; Cardiology. Vascular system; Coronary Disease - pathology; Coronary Disease - physiopathology; Coronary Vessels - pathology; Dogs; Female; Heart; Male; Medical sciences; Mitochondria; Mitochondria, Heart - metabolism; Mitochondria, Heart - ultrastructure; Myocardial ischemia; Oxidative Phosphorylation; Oxygen Consumption; Regional myocardial blood flow; Ultrastructure; Animal model; Mitochondria; Ischemia; Oxidative phosphorylation; Ultrastructure; Cardiovascular disease; Exploration; Myocardial disease; Cell respiration
• ISSN: 0047-1828; 1347-4839
• DOI: 10.1253/jcj.55.714

Myocardial blood flow (MBF). tissue ATP content. mitochondrial respiratory function and mitochondrial ultrastructure were examined in 62 adult mongrel dogs weighing 6-14kg in which acute myocardial ischemia had been produced under anesthesia. The left anterior descending coronary artery was dissected free for ligation before the first diagonal branch. MBF was measured before coronary ligation and 60 min following ligation. Then, samples of myocardium were taken and subjected to tissue ATP content assay. mitochondrial respiratory function measurement respiratory control index (RCI) and rate of oxygen consumption in state III (QO2III): and electron microscopic examination. Mitochondrial morphologic injury was evaluated quantitatively according to Schaper's criteria. MBF was significantly correlated with tissue ATP content. mitochondrial respiratory function and mitochondrial ultrastructural change. When MBF was less than 20ml/min/100g. tissue ATP content (1.86±1.21 μmol/g wet weight) and mitochondrial respiratory function (RCI 2.51±0.59) were significantly lower than in the non-ischemic area (ATP 4.52±1.11. RCI 3.82±0.37) and, mitochondrial ultrastructural injury had deteriorated significantly at an MBF below 40 ml/min/100g. In conclusion, our findings show that when MBF is reduced, mitochondrial ultrastructural changes precede the depression in mitochondrial oxidative phosphorylation.