诱发电位评价缺血性中风后脑功能的实验研究

Experimental Study in Evaluating Brain Function by Evoked Potential Following Acute Ischemic Stroke

目的:探讨缺血性中风后诱发电位(evoked potentials,EP)变化规律,及诱发电位对缺血性中风大鼠脑功能监测作用。方法:采用改良的线栓法制备大脑中动脉阻塞(middle cerebral artery occlusion,MCAO)模型,于缺血性中风后不同时间段(12h、24h、36h),检测缺血侧运动诱发电位(motor evoked potentials,MEP)、体感诱发电位(somatosensory evoked potentials,SEP),应用氢清除法观察脑缺血各组脑血流量(regional cerebral blood flow,rCBF)的变化。结果:局造性缺血后,SEP的P1、N1、P2波的波幅与夹闭前比较有不同程度的减少,波形较为稳定定,但潜伏期较夹闭前逐渐延长(P<0.01);MEP的N1,N2波潜伏期与夹闭前比较明显延长(P<0.01),波形有明显的变异;大鼠脑皮层CBF随着时间延长有下降趋势,各时间点CBF与夹闭前比较有显著下降(P<0.01)。结论:大鼠缺血性中风后SEP、MEP的潜伏期明显延长,脑血流量明显低于夹闭前。诱发电位可用于评价和监测缺血性中风后脑功能。

Objective： To study the characteristic of latency of evoked potential（EP）, and monitoring brain function by evoked potential following acute ischemic stroke in rats. Methods： The model of acute ischemic stroke in rats was made by middle cerebral artery occlusion （MCAO）. All animals of ischemic stroke were detected latency of somatosensory evoked potentials （SEP） and motor evoked potentials （MEP） after different durations of （12 h,24 h, 36 h）, the regional cerebral blood flow （rCBF） was also measured by hydrogen cleaning method after MCAO in rats. Results： The result showed that the latency of P1, N1 and P2 waves in SEP were significantly prolonged than that of previous occlusion （P〈0.01）, the amplitude of waveform in SEP were various degree decreased in various group, shape of wave in SEP were stabilized after MCAO; the latency of N1 and P2 waves in MEP were significantly prolonged than that of previous occlusion （P〈0.01）, shape of wave in MEP were aberrant after MCAO; trend ofrCBF were decreased along time, the level ofrCBF was significantly lower than that of previous occlusion （P〈0.01）. Conclusions： The latency ofSEP, MEP were significantly prolonged, the level ofrRCBF was significantly lower than that of previous occlusion following acute ischemic stroke in rats. EP might be applied to evaluate and monitor brain function following acute ischemic stroke.