Stys P K, Ashby P
Department of Electromyography, Toronto Western Hospital, University of Toronto, Ontario, Canada.
Muscle Nerve. 1990 Aug;13(8):750-8. doi: 10.1002/mus.880130814.
Action potentials conducted along a nerve fiber leave in their wake consistent alterations in excitability, including the absolute and relative refractory periods, a supernormal period (SNP) and a late phase of subnormality. We describe an automated technique for reliably determining the recovery cycle of human sensory nerve fibers by delivering series of paired stimuli and precisely measuring the latencies (to within 0.5 microseconds) of the compound action potentials. The recovery cycle can be compiled from the differences in latency between the two responses of a pair. Consistent changes in conduction velocity are demonstrated during each phase of altered excitability. Possible physiological mechanisms underlying the recovery cycle are discussed, and the effects of cold, ischemia, prior tetanization and subcutaneous lidocaine are presented. This technique may prove to be a useful and more sensitive tool for the study of certain disorders of peripheral nerves.
沿神经纤维传导的动作电位会在其后留下兴奋性的持续变化，包括绝对不应期和相对不应期、超常期（SNP）以及低常期的后期。我们描述了一种自动化技术，通过施加一系列成对刺激并精确测量复合动作电位的潜伏期（精确到0.5微秒以内）来可靠地确定人类感觉神经纤维的恢复周期。恢复周期可以根据一对反应中两个反应潜伏期的差异来编制。在兴奋性改变的每个阶段都证明了传导速度的一致变化。讨论了恢复周期潜在的可能生理机制，并介绍了寒冷、缺血、预先强直收缩和皮下利多卡因的影响。该技术可能被证明是研究某些周围神经疾病的一种有用且更敏感的工具。
