Binzoni T, Quaresima V, Barattelli G, Hiltbrand E, Gürke L, Terrier F, Cerretelli P, Ferrari M
Departments of Physiology and Radiology, Faculty of Medicine, University of Geneva, 1211 Geneva 4, Switzerland.
J Appl Physiol (1985). 1998 Oct;85(4):1244-51. doi: 10.1152/jappl.1998.85.4.1244.
Energy metabolism and interstitial fluid displacement were studied in the human gastrocnemius during three subsequent 5-min ischemia-reperfusion periods [ischemic preconditioning (IP)]. The muscle energy balance was assessed by combining near-infrared spectroscopy (NIRS) and 31P-nuclear magnetic resonance spectroscopy (31P-NMRS). The interstitial fluid displacement was determined by combining NIRS and 23Na-NMRS. No changes in total energy consumption or in the fractional contribution of the underlying energy sources (aerobic glycolysis, anaerobic glycolysis, and Lohmann reaction) were observed in the muscle during the tested IP protocol. Oxygen consumption in the muscle region of interest, as estimated by NIRS, was approximately 8 micromol . 100 g-1 . min-1 and did not change during IP. Phosphocreatine and ATP concentrations did not change over the whole experimental period. A slight but significant (P < 0.05) increase in intracellular pH was observed. Compared with the control, a 10% greater interstitial fluid content per muscle unit volume was observed at the end of the IP protocol. It is concluded that, at variance with cardiac muscle, repeated 5-min ischemia-reperfusion cycles do not induce metabolic changes in human gastrocnemius but alter the interstitial fluid readjustment. The techniques developed in the present study may be useful in identifying protocols suitable for skeletal muscle preconditioning and to explain the functional basis of this procedure.
在人体腓肠肌的三个连续5分钟缺血-再灌注期[缺血预处理（IP）]中研究了能量代谢和组织间液置换。通过结合近红外光谱（NIRS）和31P-核磁共振波谱（31P-NMRS）评估肌肉能量平衡。通过结合NIRS和23Na-NMRS测定组织间液置换。在所测试的IP方案期间，未观察到肌肉中总能量消耗或潜在能量来源（有氧糖酵解、无氧糖酵解和磷酸肌酸反应）的分数贡献发生变化。通过NIRS估计，感兴趣的肌肉区域中的氧消耗约为8微摩尔·100克-1·分钟-1，并且在IP期间没有变化。磷酸肌酸和ATP浓度在整个实验期间没有变化。观察到细胞内pH值有轻微但显著（P<0.05）的升高。与对照组相比，在IP方案结束时，每肌肉单位体积的组织间液含量增加了10%。得出的结论是，与心肌不同，重复的5分钟缺血-再灌注周期不会在人体腓肠肌中诱导代谢变化，但会改变组织间液的重新调整。本研究中开发的技术可能有助于确定适合骨骼肌预处理的方案，并解释该过程的功能基础。
