Essential Thalamic Contribution to Slow Waves of Natural Sleep
Essential Thalamic Contribution to Slow Waves of Natural Sleep
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DOI：
10.1523/jneurosci.3169-13.2013
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发表时间：
2013-12-11
影响因子：
5.3
通讯作者：
Crunelli, Vincenzo
中科院分区：
文献类型：
--
作者：
David, Franois;Schmiedt, Joscha T.;Crunelli, Vincenzo
慢波代表非快速眼动（非REM）睡眠的显著EEG特征之一，并且被认为在该行为状态期间发生的细胞和网络可塑性中起重要作用。这些自然睡眠的慢波目前被认为是由新皮层区域内的内在和突触机制专门产生的，尽管丘脑在这一关键生理节律中的作用已经被提出，但从未得到证实。结合神经元合奏记录，微透析，和光遗传学，在这里，我们表明，丘脑输出到新皮层的块显着（高达50%）降低慢波记录在非快速眼动睡眠在自由移动，自然睡眠-清醒大鼠的频率。在麻醉期间记录的EEG慢波上观察到类似的效应需要比睡眠期间更小体积的丘脑失活，在这种情况下，丘脑皮质神经元的爆发和单个动作电位几乎完全依赖于T型钙通道。在麻醉和自然睡眠期间，丘脑失活比慢波更强烈地减少纺锤波。此外，只有当丘脑T型钙通道功能活跃时，丘脑皮层神经元的选择性兴奋才能在窄频带（0.75-1.5 Hz）内强烈地携带EEG慢波。这些结果表明，在非快速眼动睡眠和麻醉过程中，丘脑微调慢波的频率，从而提供了第一个确凿的证据表明，一个动态的相互作用的新皮层和丘脑振荡器的慢波是需要充分表达这个关键的生理EEG节律。
Slow waves represent one of the prominent EEG signatures of non-rapid eye movement (non-REM) sleep and are thought to play an important role in the cellular and network plasticity that occurs during this behavioral state. These slow waves of natural sleep are currently considered to be exclusively generated by intrinsic and synaptic mechanisms within neocortical territories, although a role for the thalamus in this key physiological rhythm has been suggested but never demonstrated. Combining neuronal ensemble recordings, microdialysis, and optogenetics, here we show that the block of the thalamic output to the neocortex markedly (up to 50%) decreases the frequency of slow waves recorded during non-REM sleep in freely moving, naturally sleeping-waking rats. A smaller volume of thalamic inactivation than during sleep is required for observing similar effects on EEG slow waves recorded during anesthesia, a condition in which both bursts and single action potentials of thalamocortical neurons are almost exclusively dependent on T-type calcium channels. Thalamic inactivation more strongly reduces spindles than slow waves during both anesthesia and natural sleep. Moreover, selective excitation of thalamocortical neurons strongly entrains EEG slow waves in a narrow frequency band (0.75-1.5 Hz) only when thalamic T-type calcium channels are functionally active. These results demonstrate that the thalamus finely tunes the frequency of slow waves during non-REM sleep and anesthesia, and thus provide the first conclusive evidence that a dynamic interplay of the neocortical and thalamic oscillators of slow waves is required for the full expression of this key physiological EEG rhythm.