利用频域近红外光谱仪和磁共振谱仪测量骨骼肌能量代谢

Simultaneous Measurement of Muscle Energy Metabolism by MRS and Frequency-Domain NIR Spectroscopy

利用频域近红外光谱技术(NIRS)可以实现生物组织光学参数的实时定量测量。由于生物组织的吸收系数与组织中的血红蛋白的合氧状态有关,使得频域近红外光谱技术可以用来无损测量肌肉组织中与能量代谢过程密切相关的氧气供应与消耗这个动态平衡过程。磷磁共振谱仪(31 P MRS)是无损检测骨骼肌能量代谢的金标准。为了研究细胞内pH值(pHi)对磷酸肌酸重新合成和氧合血红蛋白恢复过程的影响,作者利用频域NIRS和31 P MRS联合进行了健康成人的踝关节曲展(plantarflexion)实验。通过动脉阻断和长时间全力运动尽量降低肌肉组织细胞内pH值。对照结果表明,细胞环境酸化(pHi=6 4 2 )明显地延长了运动停止后磷酸肌酸的重新合成和氧合血红蛋白的恢复过程。

The frequency-domain near-infrared spectrometry (NIRS) is capable of measuring the absolute absorption and reduced scattering coefficient of tissue noninvasively. This allows the quantitation of tissue hemoglobin concentration which reflects the balance between oxygen delivery and oxygen utilization of the skeletal muscle. Phosphorus magnetic resonance spectroscopy (P-31-MRS) has become a gold standard of noninvasive measurement of human skeletal muscle metabolism. The rate of phosphocreatine (PCr) resynthesis during recovery is an indicator of the rate of oxidative metabolism. The purpose of the present study was the effect of lower intracellular pH (pHi) on PCr and oxygenation recovery. The preliminary results of plantar flexion experiment on a healthy male subject show that both PCr resynthesis and reoxygenation were very much prolonged by severe acidosis (pHi = 6.42).