Central Laboratory of Biophysics, Bulgarian Academy of Sciences, Sofia, Bulgaria.
J Electromyogr Kinesiol. 1993;3(2):95-102. doi: 10.1016/1050-6411(93)90004-G.
The influence of alterations in intracellular action potential (ICAP) duration and in muscle fibre conduction velocity (CV) on the extracellular action potential (ECAP) duration was studied. The experiments were carried out on frog isolated skeletal muscle fibres. The ECAPs were recorded at different radial distances (from 0 μm to 3000 μm) to the muscle fibre membrane. Alterations in the CV were induced by changes in the temperature of the medium. The CV decrease led to increase in both ICAP duration and duration of the ECAPs recorded at different radial distances. The ECAP duration reflected changes in the ICAP duration and increased together with increase in the radial distances. The different extent of alteration in ICAP duration and CV following potassium conductivity blockage was used as a model for separately studying the effects of these two parameters on the ECAP duration. The duration of the ECAP in the vicinity of the fibre reflected changes in the ICAP rising time (Rt), and were practically independent of alterations of the CV. The ECAP duration at large radial distance depended on CV alterations and on radial distance.
研究了细胞内动作电位 (ICAP) 持续时间和肌纤维传导速度 (CV) 的变化对细胞外动作电位 (ECAP) 持续时间的影响。实验在离体蛙骨骼肌纤维上进行。在不同的径向距离（从 0 μm 到 3000 μm）记录 ECAP。通过改变介质温度来诱导 CV 的变化。CV 的降低导致 ICAP 持续时间和在不同径向距离记录的 ECAP 持续时间的增加。ECAP 持续时间反映了 ICAP 持续时间的变化，并随着径向距离的增加而增加。钾电导率阻断后 ICAP 持续时间和 CV 的不同程度变化被用作单独研究这两个参数对 ECAP 持续时间的影响的模型。纤维附近的 ECAP 持续时间反映了 ICAP 上升时间 (Rt) 的变化，并且实际上与 CV 的变化无关。大径向距离处的 ECAP 持续时间取决于 CV 的变化和径向距离。
