溫度對大白鼠肌纖維傳導速度之影響

The Effect of Temperature on Conduction Velocity of Muscle Fiber in Rats

韓德生(Der-Sheng Han) ； 李志明(Chih-Ming Li) ； 張權維(Chein-Wei Chang)

《台灣醫學》 7卷5期 (2003/09) Pp. 701-707

https://doi.org/10.6320/FJM.2003.7(5).04

摘要

Muscle fiber conduction velocity (MFCV) is the electrophysiological parameter representing the propagating velocity of muscle fiber action potentials. It is affected by ambient temperature. In order to measure the MFCV along rat quadriceps muscle in situ, stimulation was performed distally in the quadriceps muscle with a Tungsten microelectrode as active electrode and a monopolar electrode as reference. The single fiber EMG electrode, as a recording electrode, was inserted into the origin of quadriceps muscle. The average MFCV calculated as interelectrode distance divided by latency of 27 muscle fibers in 7 male Wistar rats, 16-24 weeks of age, of the same litter was 7.29±1.78 m/sec. The MFCVs between the right and left limbs were not different statistically. By changing the ambient temperature with thermostat and iced water, the study result showed a significant relationship between the intramuscular temperature and MFCV with correlation coefficients ranging from 0.81 to 0.96 in the 10 tested muscle fibers. The overall correlation coefficient of all sampled muscle fiber is 0.324 (p＜0.0001). However, more diverse relationship was observed between the intramuscular temperature and the amplitude of muscle fiber action potential among the 10 tested muscle fibers. Four of them are negatively related, two are positively related, and the remains are not related significantly. It was concluded that the measurement of MFCV with Tungsten microelectrode was feasible and precise. The MFCV was positively related with intramuscular temperature, but no linear relationship was observed between the amplitude of muscle fiber action potential and the intramuscular temperature.

關鍵字

肌纖維傳導速度 ； 肌肉內溫度 ； 鎢絲微電極

並列摘要

Muscle fiber conduction velocity (MFCV) is the electrophysiological parameter representing the propagating velocity of muscle fiber action potentials. It is affected by ambient temperature. In order to measure the MFCV along rat quadriceps muscle in situ, stimulation was performed distally in the quadriceps muscle with a Tungsten microelectrode as active electrode and a monopolar electrode as reference. The single fiber EMG electrode, as a recording electrode, was inserted into the origin of quadriceps muscle. The average MFCV calculated as interelectrode distance divided by latency of 27 muscle fibers in 7 male Wistar rats, 16-24 weeks of age, of the same litter was 7.29±1.78 m/sec. The MFCVs between the right and left limbs were not different statistically. By changing the ambient temperature with thermostat and iced water, the study result showed a significant relationship between the intramuscular temperature and MFCV with correlation coefficients ranging from 0.81 to 0.96 in the 10 tested muscle fibers. The overall correlation coefficient of all sampled muscle fiber is 0.324 (p＜0.0001). However, more diverse relationship was observed between the intramuscular temperature and the amplitude of muscle fiber action potential among the 10 tested muscle fibers. Four of them are negatively related, two are positively related, and the remains are not related significantly. It was concluded that the measurement of MFCV with Tungsten microelectrode was feasible and precise. The MFCV was positively related with intramuscular temperature, but no linear relationship was observed between the amplitude of muscle fiber action potential and the intramuscular temperature.

並列關鍵字

muscle fiber conduction velocity ； intramuscular temperature ； Tungsten microelectrode