Integrative mechanisms of excitation and inhibition of the motor cortex and supplementary

我们研究了人类和大鼠运动皮质和辅助感觉运动区的兴奋和抑制的综合机制，得到了以下结果：慢性硬膜下电极覆盖运动皮层和辅助感觉运动区电刺激对难治性癫痫患者运动功能的影响：人运动皮层的兴奋和抑制机制参与运动诱发电位（MEP）和沉默期（SP）的诱发。然而，负运动区和补充感觉运动区与SP.2的激发无关。反射性肌阵挛患者感觉和运动皮质间的传导时间：用两种方法估计感觉和运动皮质间的传导时间（皮质延迟）。一种方法是利用磁刺激感觉和运动皮层诱发的MEP潜伏期的不同时间。另一种方法是测量C反射、SEP （N20）和MEP，根据P潜伏期计算皮层延迟（皮质延迟C反射- N20 - MEP）。从这些研究中可以看出，感觉和运动皮层之间的传导时间约为4 msec，并且皮层反射性肌阵挛患者与皮质基底变性患者的C反射（长环反射）通路不同。从大鼠脑内电压门控钠通道活动分析脑功能：连续7天（总刺激次数10500次）重复经颅磁刺激（rTMS，刺激次数1500次/天）后，大鼠脑内电压门控钠通道活动立即显著增加。此外，这些活动在rTMS后第14天显著增加，并在刺激后第28天恢复到基线水平。rTMS后电压门控钠通道数量稳定。另一方面，大鼠海马电压门控钠通道的活性在rTMS后没有明显增加。这些结果表明rTM引起的这些活动的变化在大鼠脑内是可逆的。难治性颞叶癫痫患者颞叶内侧电压门控钠通道数量明显减少，但这些活动在正常水平。这些结果表明，这些患者的海马体没有过度兴奋。经颅磁刺激运动皮层所引起的MEP研究尚未证实人体存在锥体对话。毫无疑问，运动皮层支配着一些患者的上肢和下肢同侧肌肉。此外，体感通路也会上升到同侧感觉皮层（3b区），这已被SEP研究证实。少

We studied the integrative mechanisms of excitation and inhibition of motor cortex and supplementary sensorimotor areas in human and rat in which the following results were obtained.1. Motor function by the electrical stimulation of chronic subdural electrodes covering the motor cortex and supplementary sensorimotor areas in the patients with intractable epilepsy :The excitation and inhibition mechanisms of the motor cortex in human participate in eliciting motor evoked potentials (MEP) and silent period (SP). However, the negative motor area and supplementary sensorimotor areas have no concern with elicitation of SP.2. Conduction time between sensory and motor cortices in the patients with reflex myoclonus :The conduction time (cortical delay) between sensory and motor cortices was estimated by two methods. The one method was different time between two MEP latencies elicited by magnetic stimulation of sensory and motor cortices. The other was measurements of C reflex, SEP (N20) and ME … More P latencies from which calculated the cortical delay (cortical delay C reflex - N20 - MEP). It becomes evident from these studies that the conduction time between sensory and motor cortices is approximately 4 msec, and the pathways of C reflex (long loop reflex) are different between the patients with cortical reflex myoclonus and those with corticobasal degeneration.3. Brain function analyzing from the activities of voltage-gated sodium channels in rat brain :The activities of voltage-gated sodium channels in the rat brain were significantly increased immediately after the repetitive transcranial magnetic stimulation (rTMS, number of stimuli : 1,500/day) for 7 days consecutively (total number of stimuli : 10,500). Furthermore, those activities were significantly increased at 14th day after the rTMS, and returned to the baseline levels at 28th day after the stimulation. The number of voltage-gated soduim channels were stable after the rTMS.On the other hand, the activities of voltage-gated sodium channels at the hippocampus in the rat were not significantly increased after the rTMS.These results suggest that the changes of these activities evoked by rTM are reversible in the rat brain. The number of voltage-gated sodium channels were decreased significantly at the mesial temporal lobe in the patients with intractable temporal lobe epilepsy, although these activities were in normal levels. These results suggest that there is no excessive excitation in the hippocampus in those patients.4. No pyramidal decussation in human has been proved by the study of MEP elicited by transcranial magnetic stimulation of the motor cortex. The motor cortex undoubtedly innervates ipsilateral muscles of the upper and lower extremities in some patients. Furthermore, somatosensory pathways also ascends to the ipsilateral sensory cortex (3b area) without decussation in those subjects which has been proved by SEP study. Less