Fukuda H
Department of Cardiovascular Medicine, Hokkaido University School of Medicine, Sapporo, Japan.
Hokkaido Igaku Zasshi. 1989 Jul;64(4):466-73.
The relationship between the energy state and intracellular oxygen concentration was established in the cardiac tissues, where the former could be monitored by 31PNMR and latter by optical method for myoglobin absorption. The ratio of creatine phosphate to inorganic phosphate (PCr/Pi), started to fall at 40 microM ofintacellular oxygen concentration. In contrast, intracellular pH and cardiac function started to fall at 10 microM of oxygen. By infusion of epinephrine (0.01 micrograms/min), myoglobin was deoxygenated concomitant with the increase of left ventricular pressure and heart heart rate increased. The oxygen dependence of Parameters described above were unchanged by epinephrine infusion. Araki et al. reported that oxygen consumption, the reduction of pyridine nucleotide, the increase of lactate release started to change at 10 microM and reduction of cytochrome a + a3 started to increase at 40 microM. These results suggest that there is near-equilibrium state in the respiratory chain and oxidative phosphorylation in the cardiac tissue. The decrease of oxygen consumption was compensated by PCr/Pi ratio and cytochrome a + a3. And this near-equilibrium was maintained when the respiratory rate increased.
在心脏组织中建立了能量状态与细胞内氧浓度之间的关系，其中前者可通过31P核磁共振监测，后者可通过肌红蛋白吸收的光学方法监测。磷酸肌酸与无机磷酸的比值（PCr/Pi）在细胞内氧浓度为40微摩尔时开始下降。相比之下，细胞内pH值和心脏功能在氧浓度为10微摩尔时开始下降。通过输注肾上腺素（0.01微克/分钟），肌红蛋白脱氧，同时左心室压力增加，心率加快。上述参数的氧依赖性不受肾上腺素输注的影响。荒木等人报告说，氧消耗、吡啶核苷酸的还原、乳酸释放的增加在10微摩尔时开始变化，细胞色素a + a3的还原在40微摩尔时开始增加。这些结果表明，心脏组织中的呼吸链和氧化磷酸化存在近平衡状态。氧消耗的减少由PCr/Pi比值和细胞色素a + a3补偿。当呼吸速率增加时，这种近平衡得以维持。
