摘要
目的:通过动物实验,探讨间断性迷走神经刺激(vagusnervestimulation,VNS)控制癫痫的最佳启动时间及其抗痫效果,观察VNS对海人藻酸致痫大鼠皮质电图和海马神经元电活动的影响。方法:实验选用成年、健康、体质量220～250g的Wistar大鼠,40g/L戊巴比妥钠腹腔麻醉后,颈部皮下注射海人藻酸(10mg/kg)复制癫痫模型。在癫痫发作前后分别给予大鼠左侧迷走神经间断刺激,用银球电极与金属微电极分别记录皮质电图和海马CA1区神经元电活动的变化。结果:①癫痫发作前给予VNS刺激(3.0～4.0mA,33Hz,1ms)50min,皮质电图结果表明可显著降低癫痫发作的严重程度,缩短发作持续时间,甚至可完全抑制发作(F=27.32,P<0.001)。而癫痫一旦发生再给予上述刺激,则只能降低发作的严重程度,而不能完全阻抑癫痫发作。②当皮下注射海人藻酸诱发海马CA1区神经元出现典型的不规则爆发样电活动后,给予上述刺激,CA1区神经元放电频率有所减少,停止VNS60min和120min后,放电频率继续显著下降(F=8.531,P<0.05)。结论:①阻抑海人藻酸致痫模型发作,VNS启动越早,抗痫作用越佳。
AIM:To explore the best startup time of controlling epilepsy with vagus nerve stimulation(VNS) and its effect through animal experiment, and observe the effect of VNS on electrocorticogram(EGoG) and electrical activity of hippocampal neurons in epileptic rats induced by kainic acid(KA). METHODS:Adult healthy Wistar rats, weighed 220-250 g,were under intraperitoneal anesthesia with soluble pentobarbitone(40 g/L),then were injected subcutaneously KA(10 mg/kg,Sigma) for replication of epilepsia model.The left vagus nerves were stimulated with intermittent current pulses before and after seizures,The ECoG of frontal cortex and evoked discharges of CA1 area in hippocampus were recorded by silver ball electrode and metal microelectrode, respectively. RESULTS:①The intensity and duration of ECoG were reduced,shortned and even disappeared completely in some cases by VNS with pulse of 3-4 mA,33 Hz,1 ms before seizures(F=27.32,P< 0.001).The same stimulation was given when seizure reoccurred,it could only be reduced the degree but couldn't disappear completely.②The same stimulation was given when the burst discharges of CA1 in hippocampus induced by injecting subcutaneously KA appeared.The discharging frequency decreased,and continued to reduce 60 min and 120 min after stopping VNS(F=8.531,P< 0.05).The result showed that if discontinuous VNS were given as early as possible,anti epileptic effect was significant,and VNS could inhabit epileptic discharge of hippocampal neurons effectively. CONCLUSION:①The earlier VNS is used,the better the repression of seizure of epileptic models induced by KA is.②Anti epileptic effect of discontinuous VNS on epileptic rats induced by KA,may be caused by continuous discharge of hippocampal neurons of CA1,which shows that hippocampal formation plays an important role in anti epileptic effect of VNS.
出处
《中国临床康复》
CSCD
2003年第31期4226-4227,共2页
Chinese Journal of Clinical Rehabilitation
基金
北京市教育委员资助课题(1998)~~
