离体青蛙骨骼肌中的阶梯式增强：诱发复合肌肉动作电位的功率谱分析

Staircase potentiation in isolated frog skeletal muscle: power spectral analysis of the evoked compound muscle action potential.

Barnes W S, Williams J H

Department of Health and Kinesiology, Texas A&M University, College Station 77843.

Comp Biochem Physiol A Comp Physiol. 1990;96(3):387-94. doi: 10.1016/0300-9629(90)90101-w.

Abstract

The mechanical and electrophysiological effects of repetitive, low-frequency electrical stimulation on paired sartorii muscles from small male frogs have been investigated, in vitro. 2. Stimulation for 90 sec at 5 Hz resulted in a progressive rise (staircase) than fall (fatigue) in peak twitch tension. 3. The root mean square amplitude, peak-to-peak amplitude, conduction velocity and mean power frequency of evoked compound muscle action potentials (CMAPs) decreased over the stimulation period. 4. Results suggest that alterations in the shape of the CMAP during repetitive stimulation may contribute to the staircase phenomenon.

摘要

已在体外研究了重复性低频电刺激对小型雄性青蛙成对缝匠肌的机械和电生理效应。2. 以5赫兹刺激90秒导致峰值抽搐张力逐渐上升（阶梯现象）而非下降（疲劳）。3. 在刺激期间，诱发的复合肌肉动作电位（CMAP）的均方根振幅、峰峰值振幅、传导速度和平均功率频率均降低。4. 结果表明，重复性刺激期间CMAP形状的改变可能导致阶梯现象。