Sims M H
Am J Vet Res. 1982 Jan;43(1):89-93.
The recovery cycle for a reflex-evoked muscle potential has been demonstrated in the healthy dog, using the ulnar nerve-interosseous muscle preparation. The amplitude of a test response, at various time intervals (2 to 1,000 ms) after a conditioning response, was compared with the amplitude of the unconditioned response. The resulting ratio was plotted as a function of interstimulus interval. The curve was shown to consist of 3 distinct phases. The 1st phase, called the phase of early responsiveness, lasted from 2 to 20 ms and was characterized by a rapid decrease in amplitude of the test response. The 2nd phase, the phase of unresponsiveness, was characterized by a reduced response, and eventually no response which occurred between 20 and 80 ms. The 3rd phase, the phase of late responsiveness, began with a small test reflex amplitude at 80 ms and increased to 200 ms where it plateaued thereafter. Between 200 and 1,000 ms, there was no significant change in amplitude. Only at 2 ms, where the conditioning and test responses were so close together that they fused, did the mean amplitude of the test response exceed the mean unconditioned response. The reflex-evoked muscle potential recovery curve provides additional proof that the reflex is the equivalent of the H-reflex, and it provides a quantitative measure of spinal cord lower motor neuron excitability in the dog.
利用尺神经-骨间肌标本，已在健康犬身上证实了反射诱发肌肉电位的恢复周期。在条件反应后的不同时间间隔（2至1000毫秒）测量测试反应的幅度，并与非条件反应的幅度进行比较。将所得比率绘制成刺激间隔的函数。结果表明，该曲线由三个不同阶段组成。第一阶段称为早期反应阶段，持续2至20毫秒，其特征是测试反应的幅度迅速下降。第二阶段为无反应阶段，其特征是反应减弱，最终在20至80毫秒之间无反应。第三阶段为晚期反应阶段，在80毫秒时以较小的测试反射幅度开始，增加到200毫秒后趋于平稳。在200至1000毫秒之间，幅度无显著变化。只有在2毫秒时，条件反应和测试反应非常接近以至于融合，测试反应的平均幅度才超过非条件反应的平均幅度。反射诱发肌肉电位恢复曲线进一步证明了该反射等同于H反射，并且它提供了犬脊髓下运动神经元兴奋性的定量测量方法。
