不同频率和持续时间经皮电刺激耳甲区对大鼠癫痫发作抑制作用的比较

Effects of Transcutaneous Electrostimulation of Auricular Concha at Different Stimulating Frequencies and Duration on Acute Seizures in Epilepsy Rats

目的:比较不同频率经皮电刺激耳甲区对大鼠癫痫发作的影响,以明确不同刺激频率及刺激持续时间所产生的抑制效应的差别。方法:健康成年SD大鼠44只,随机按刺激持续的时间长度分为4组:30s组、5min组、10min组和30min组,每组9～12只。以腹腔注射戊四氮造成大鼠急性癫痫模型,记录动物癫痫发作前后大脑皮层场电位信号,以刺激后癫痫发作被抑制的后效应持续时间和刺激结束后以30s为单位时间统计10个单位时间段内大鼠癫痫发作率为指标,观察不同频率(2Hz、20Hz和100Hz)的耳甲区经皮电刺激对大鼠癫痫发作抑制作用的差别。结果:(1)20Hz的耳甲区经皮电刺激在所有刺激持续时间中平均后效应持续时间为(169.50±45.96)s,和2Hz、100Hz刺激频率后效应持续时间(50.12±21.38)s和(67.44±23.92)s相比,刺激后抑制癫痫发作的持续时间较长(P<0.05);(2)在2Hz刺激条件下,30s组抑制癫痫发作的后效应持续时间较长(P<0.01),癫痫发作率下降,与其它刺激持续时间组相比差异具有统计学意义(P<0.05);(3)在100Hz刺激条件下,30min组抑制癫痫发作的后效应持续时间较长(P<0.01),癫痫发作率下降,与其它刺激持续时间组相比差异具有统计学意义(P<0.05)。结论:耳甲区经皮电刺激能明显抑制大鼠癫痫发作,20Hz的刺激频率对大鼠癫痫模型的治疗作用较好,2Hz的刺激频率在短期刺激后表现出较好的治疗作用,100Hz的刺激频率在长期刺激后才能表现出较好的治疗作用。

Objective To observe the inhibitory effect of auricular concha transcutaneous electrostimulation （ACTES） of different frequencies and duration on acute seizures in epilepsy rats so as to select a better stimulating parameter for relieving epi- lepsy. Methods According to the stimulation duration of ACTES, 44 Sprague-Dawley rats were randomized into：30 s, 5 min, 10 min, and 30 min groups. Epilepsy model was duplicated by intraperitoneal injection of PTZ （pentylenetetrazol, 50 mg/kg）. Cerebral field potentials delivered from the fixed 4 recording electrodes array （A-P： -3-6, L.. 4-6, H： 1.5） and re-ference electrode （a fixed screw） touching the cerebral dura surface were recorded using a data acquisition system （CerebusTM 5.0 sys- tem）. Transcutaneous electrostimulation （1 mA, duration 500 IaS） of frequency 2 Hz, 20 Hz and 100 Hz was applied to auricular concha by using an electric stimulator. The anti-epileptic effects of ACTES were evaluated by using the duration and rate of seizure suppression. Results （1）The anti-epileptic effect of 20 Hz -ACTES was markedly longer than those of 2 Hz and 100 Hz in the duration of seizure suppression （P〈0.05）. （2） After 2 Hz-ACTES, the anti-epileptic effects （duration and inhibitory rate） in 30 s-stimulation group were markedly longer than those of the 5 min-, 10 min- and 30 min-stimulation groups （ P〈0.01, P〈0.05）. （3） After 100 Hz-ACTES, the anti-epileptic effects （duration and rate of seizure suppression） in the 30 min-stimulation group were markedly longer than those in the 30 s-, 5 min- and 10 min-stimulation group （P〈0. 01, P〈0. 05）. Conclusion ACTES at 20 Hz can effectively lessen epileptic seizures, and under fixed stimulating frequencies of 2 Hz and 100 Hz, the anti-epi- leptic effects of 30 s ACTES and 30 min-ACTES are obviously better in epilepsy rats.