Stability of neocortical synapses across sleep and wake states during the critical period in rats.
Stability of neocortical synapses across sleep and wake states during the critical period in rats.
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DOI：
10.7554/elife.66304
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发表时间：
2021-06-21
期刊：
影响因子：
7.7
通讯作者：
Turrigiano GG
中科院分区：
文献类型：
--
作者：
Cary BA;Turrigiano GG
睡眠对大脑的可塑性很重要，但它的确切功能仍然是个谜。一个有影响力但有争议的观点是，睡眠的一个关键功能是推动兴奋性突触强度的普遍降低。在这里，我们使用实时睡眠分类、突触后强度的体外测量和丘脑皮质突触效能的在体光遗传学监测来询问睡眠和清醒状态是否可以结构性地驱动幼年大鼠新皮质内突触强度的变化。我们发现，L4和L2/3锥体神经元上的微型兴奋性突触后电流在初级视觉(V1)和前额叶皮质(PFC)的睡眠和清醒密集时期都是稳定的。此外，对行为自由的动物的V1区丘脑皮质突触效能的长期监测显示，即使是在自然睡眠和清醒的较长时期，反应也是稳定的。综上所述，这些数据表明，在幼年动物高度可塑性的关键时期，睡眠并不会导致突触强度的普遍降低。这种在睡眠和醒来时的非凡稳定性是否适用于完全成熟的神经系统，还有待观察。
Sleep is important for brain plasticity, but its exact function remains mysterious. An influential but controversial idea is that a crucial function of sleep is to drive widespread downscaling of excitatory synaptic strengths. Here, we used real-time sleep classification, ex vivo measurements of postsynaptic strength, and in vivo optogenetic monitoring of thalamocortical synaptic efficacy to ask whether sleep and wake states can constitutively drive changes in synaptic strength within the neocortex of juvenile rats. We found that miniature excitatory postsynaptic current amplitudes onto L4 and L2/3 pyramidal neurons were stable across sleep- and wake-dense epochs in both primary visual (V1) and prefrontal cortex (PFC). Further, chronic monitoring of thalamocortical synaptic efficacy in V1 of freely behaving animals revealed stable responses across even prolonged periods of natural sleep and wake. Together, these data demonstrate that sleep does not drive widespread downscaling of synaptic strengths during the highly plastic critical period in juvenile animals. Whether this remarkable stability across sleep and wake generalizes to the fully mature nervous system remains to be seen.