Pathophysiological investigation of respiratory failure;Changes in energy metabolism using ^<31>P-NMR method

1. 为了研究细胞对慢性缺氧的能量代谢适应情况，采用荧光素-荧光素酶法测定了培养的肺泡和腹膜巨噬细胞中高能磷酸化合物的浓度。肺泡巨噬细胞和腹膜巨噬细胞中ATP蛋白含量差异无统计学意义。肺泡巨噬细胞培养48小时。在有氧和无氧条件下。与好氧培养的巨噬细胞相比，厌氧培养的巨噬细胞ATP减少20%。磷酸肌酸（CP）和能量电荷无显著差异。这些结果表明，在厌氧培养的巨噬细胞中，ATP的产生由于氧化磷酸化的抑制而减少。将Wister大鼠置于常压缺氧条件下6 W。采用荧光素-荧光素酶法和^<31>P-NMR谱法测定对照组和缺氧大鼠大腿上部肌肉的高能磷酸化合物。在两种方法下，正常大鼠和缺氧大鼠体内高能磷酸化合物含量均无差异。研究了正常受试者和慢性呼吸衰竭患者在运动过程中高能磷酸化合物的变化。这些受试者将手臂置于核磁共振波谱的磁体中，并被要求等压收缩3分钟。^<31> p -核磁共振波谱在休息、运动和恢复期间每3分钟测量一次。运动时无机磷酸盐峰值升高并向CP峰偏移，CP峰降低。慢性呼吸衰竭患者运动时细胞内PH值比正常人下降更明显，运动时CP/Pi比正常人低。这些结果表明，在运动过程中，患者的无氧代谢可能比正常人更活跃。

1. To investigate the cellular acclimatization of energy metabolism to chronic hypoxia, concentration of high energy phosphate compounds of cultivated alveolar and peritoneal macrophages were measured by Luciferin-Luciferase methods. ATP contained 1mg of protein in alveolar and peritoneal macrophages was not significantly different. Alveolar macrophages were cultivated for 48 hr. under aerobic and anaerobic conditions. ATP in anaerobically cultivated macrophage is decreased by 20% compared with aerobically cultivated one. Creatine phosphate (CP) and energy charge were not significantly different. These results suggest that production of ATP is decreased in anaerobically cultivated macrophages due to inhibition of oxidative phosphorylation.2. Wister rats were exposed to normobaric hypoxic condition for 6 W. High energy phosphate compounds of upper thigh muscle in control and hypoxic rats were measured by Luciferin-Luciferase methods and ^<31>P-NMR spectroscopy. There is no difference of high energy phosphate compounds between control and hypoxic rats in both methods.3. Normal subject and patients with chronic respiratory failure were studied for the changes of high energy phosphate compounds during exercise. These subjects placed their arm into the magnet of the NMR spectroscopy and were asked to contract isotonically for 3 min. ^<31>P-NMR spectrum were taken every 3 min at rest, during exercise and recovery. During exercise, peak of inorganic phosphate increased and deviated to CP peak, and the CP peak decreased. In patients with chronic respiratory failure, intracellular PH decreased more remarkably than normal subject, CP/Pi during exercise was lower than that in normal subject. These results indicate that anaerobic metabolism in the patients may be activated more during exercise than in normal subject.