蟾蜍脊神经节神经元对外周重复刺激的反应

本工作用细胞内记录技术,研究并分析了蟾蜍离体脊神经节神经元对重复刺激其外周突(坐骨神经)的反应。所记录的66个神经元的传导速度,刺激阈值和静息膜电位分別为5.3—20.0m/s,0.02—0.10mA 和-50—-80mV。随着重复刺激频率的增加,脊神经节神经元的细胞内动作电位进行性地出现潜伏期动摇或延迟、振幅降低、后超极化减弱和时程延长。与此同时,锋电位分解成 S、NM 和 M 三种亚波成分,并进而出现脱失。S、NM 和 M 成分对刺激频率的跟随能力为 S

RESPONSES OF TOAD SPINAL GANGLION NEURONS IN VITRO TO PERIPHERAL REPETITIVE STIMULATION

Responses of toad ganglion neurons in vitro to repetitive stimulation of their peripheral processes (sciatic nerve) were intracellularly recorded. The conduction velocity, threshold and resting membrane potential of the 66 recorded neurons ranged 5.3-20.0 m/s, 0.02-0.10 mA, and -50-(-)80 mV, respectively. As the stimulation frequency increased, jitter or delay in onset latency, reduction in amplitude, prolongation in duration, and decrease in afterhyperpolarization occurred in evoked responses of the spinal ganglion neurons. The responses decomposed into three subwaves of S, NM, and M and then missed. The ability of these three components to follow stimulation frequency was in the order of S less than NM less than M; the frequency range during which the spike potential or wave S misses was from 16.7 Hz to 250 Hz. These results indicate that there are three distinct zones in excitability in type A toad spinal ganglion neurons, and some of them may exhibit synaptic or junctional activity.