The role of the thalamus in vigilance and epileptogenic mechanisms
The role of the thalamus in vigilance and epileptogenic mechanisms
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DOI：
10.1016/s1388-2457(00)00398-9
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发表时间：
2000-09-01
影响因子：
4.7
通讯作者：
de Curtis, M
中科院分区：
文献类型：
--
作者：
Avanzini, G;Panzica, F;de Curtis, M
目的：综述了与睡眠纺锤波和尖波放电有关的丘脑节律发生机制的解剖生理基础的研究成果。方法：对猫、啮齿动物和其他哺乳动物进行体内或体外电生理记录实验。结果：睡眠纺锤波和尖波放电的节律性双侧和同步脑电图活动与相互连接的皮层和丘脑神经元的振荡模式相关。当膜电位（由胺能和胆碱能系统调节）被设置到一个低阈值钙电流失活的水平时，丘脑神经元就会产生这些节律模式。负责启动丘脑皮层振荡活动的起搏器结构已被确定为网状丘脑核，这是一种只投射到其他丘脑核的氨基丁酸能结构。在斯特拉斯堡的遗传性缺失癫痫大鼠中进行的实验表明，遗传性缺失癫痫大鼠模型中丘脑核起搏器特性的增强是由于基因决定的低阈值钙电流的增加，这是导致峰波放电病理同步的原因。结论：最近的实验证实了长期存在的假设，即纺锤波和尖波放电具有涉及丘脑-皮层回路的共同机制。由于其独特的解剖和功能结构，丘脑网状核在这些节律性脑电图活动中起着至关重要的起搏器作用。(C) 2000爱思唯尔科学爱尔兰有限公司版权所有。
Objectives: The most relevant results of studies on the anatomo-physiological substrate of the thalamic rhythmogenic mechanisms responsible for sleep spindles and spike-wave discharges are reviewed.Methods: The reviewed experiments have been carried out in cats, rodents and other mammals with either in vivo or in vitro electrophysiological recording.Results: The rhythmic bilateral and synchronous EEG activities underlying sleep spindles and spike-wave discharges have been found to be correlated with oscillatory patterns involving mutually interconnected cortical and thalamic neurons. These rhythmic patterns are generated in thalamic neurons when the membrane potential, which is modulated by aminergic and cholinergic systems, is set to a level where the low threshold calcium current is de-inactivated. The pacemaker structure responsible for the initiation of the thalamo-cortical oscillatory activities has been identified as the reticular thalamic nucleus, a GABAergic structure projecting exclusively to the other thalamic nuclei. Experiments carried out in GAERS (genetic absence epilepsy rat from Strasbourg) demonstrated in this rat model of inherited absence epilepsy an enhancement of the pacemaker properties of the thalamic nucleus, due to a genetically determined increase in the low threshold calcium current, which is responsible for the pathological synchronization underlying spike-wave discharges.Conclusions: Recent experiments confirm the longstanding hypothesis that spindles and spike-wave discharges share common mechanisms involving thalamo-cortical circuitry. Due to its unusual anatomic and functional organization the nucleus reticularis thalami plays a crucial role as pacemaker of these rhythmic EEG activities. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.