不同波形低频率电刺激对小鼠海马电点燃癫痫的作用比较

目的:观察比较不同脉冲波形的低频率电刺激对海马电点燃癫痫模型小鼠的作用差异。方法:采用电点燃刺激法建立小鼠癫痫模型,观察正弦波、单相方波、双相方波低频率电刺激对模型小鼠癫痫行为发作及后放电持续时间的影响,并比较不同时间点给予正弦波低频率电刺激的抗癫痫作用。结果:与对照组比较,正弦波低频率电刺激30 s 能降低小鼠海马电点燃癫痫发作等级(2.85 ± 0.27 vs 4.75 ±0.12,P<0.05)、减少大发作概率(53.6% vs 96.5%,P< 0.01)和缩短后放电持续时间[(16.22 ± 1.69)s vs (30.29 ± 1.12)s,P<0.01],而单相方波和双相方波低频率电刺激30 s没有明显的抗癫痫作用。常用的单相方波低频率电刺激15 min能降低小鼠海马电点燃发作等级(3.58 ± 0.16,P<0.05)、减少大发作概率(66.7%,P<0.01);但对海马后放电持续时间及大发作持续时间无影响(均P>0.05)。此外,电点燃刺激前预先给予或结束后3 s内给予正弦波低频率电刺激具有明显的抗癫痫作用(P<0.05或P<0.01),而电点燃刺激结束10 s给予正弦波低频率电刺激则无上述抗癫痫作用。结论:低频率电刺激抗癫痫作用受波形参数的影响,其中正弦波低频率电刺激能有效抑制小鼠海马电点燃癫痫的发作。
Abstract: Objective: To investigate whether the waveform of electrical stimulus affects the antiepileptic effect of focal low-frequency stimulation (LFS). Methods: The antiepileptic effects of the LFS in sine, monophase square and biphase square waves were investigated in hippocampal kindled mice, respectively. Results: Compared to the control group, sine wave focal LFS(30 s) inhibited seizure stages(2.85±0.27 vs 4.75±0.12,P<0.05), lowered incidence of generalized seizures(53.6% vs 96.5%,P<0.01) and reduced afterdischarge durations[(16.22±1.69)s vs (30.29±1.12)s,P<0.01] in hippocampal kindled mice, while monophase or biphase square wave LFS (30 s) showed no antiepileptic effect. Monophase square LFS(15 min) inhibited seizure stages(3.58 ± 0.16,P<0.05) and incidence of generalized seizures(66.7%,P<0.01), but had weaker inhibitory effect on hippocampal afterdischarge durations than sine wave LFS. In addition, pre-treatment and 3 s but not 10 s post-treatment with sine wave LFS resulted in suppression of evoked seizures(P<0.05 or P<0.01). Conclusion: The antiepileptic effect of LFS is dependent on its waveform. Sine wave may be optimal for closed-loop LFS treatment of epilepsy. Key words: Epilepsy/therapy Electric stimulation therapy Disease models, animal