Argov Z, De Stefano N, Arnold D L
Department of Neurology, Hebrew University, Hadassah Medical School, Jerusalem, Israel.
NMR Biomed. 1996 Jun;9(4):165-72. doi: 10.1002/(SICI)1099-1492(199606)9:4<165::AID-NBM408>3.0.CO;2-X.
The pattern of cytosolic ADP recovery after exercise has not been fully characterized in human skeletal muscle. ADP recovery after brief, ischemic exercise was studied by 31phosphorus magnetic resonance spectroscopy in calf muscles of 33 normal control subjects, four patients with McArdle's disease and 13 patients with mitochondrial myopathy. In normal muscle, the half-time for the initial ADP decline was 0.18 +/- 0.07 min and was unaffected by the pH or the metabolic state at the end of exercise. ADP decreased to below rest values during the second min of recovery in 27 out of 33 control subjects. There was a significant (p < 0.001) linear correlation for both the size (r = 0.65) and duration (r = 0.64) of this ADP undershoot with intracellular pH. Phosphocreatine resynthesis continued during the ADP undershoot. ADP undershoot was also found in patients with mitochondrial diseases (in 11 out of 13), but not McArdle's disease (six patients). Thus ADP recovery follows a complex time course that is partly dependent on pH. Only the initial ADP recovery is independent of pH, which makes it suitable for comparative assessment of muscle mitochondrial function in vivo. As phosphocreatine recovery continues during the ADP undershoot, mitochondrial regulation must be different from that at the onset of recovery. These observations are consistent with variable, changing regulators of mitochondrial metabolism in human skeletal muscle.
运动后胞质ADP恢复模式在人类骨骼肌中尚未得到充分表征。通过31磷磁共振波谱对33名正常对照受试者、4名麦克尔迪氏病患者和13名线粒体肌病患者的小腿肌肉进行短暂缺血运动后的ADP恢复情况进行了研究。在正常肌肉中，初始ADP下降的半衰期为0.18±0.07分钟，且不受运动结束时pH值或代谢状态的影响。在33名对照受试者中，有27名在恢复的第二分钟内ADP降至静息值以下。这种ADP下降的幅度（r = 0.65）和持续时间（r = 0.64）与细胞内pH值均存在显著（p < 0.001）线性相关性。在ADP下降期间磷酸肌酸持续再合成。线粒体疾病患者（13名中有11名）也出现了ADP下降，但麦克尔迪氏病患者（6名）未出现。因此，ADP恢复遵循复杂的时间进程，部分取决于pH值。只有初始ADP恢复与pH值无关，这使其适合用于体内肌肉线粒体功能的比较评估。由于在ADP下降期间磷酸肌酸恢复仍在继续，线粒体调节必定与恢复开始时不同。这些观察结果与人类骨骼肌中线粒体代谢的可变、变化的调节因子一致。
