Niethard Niels, Hasegawa Masashi, Itokazu Takahide, Oyanedel Carlos N, Born Jan, Sato Takashi R
Institute for Medical Psychology and Behavioral Neurobiology, University of Tübingen, 72076 Tübingen, Germany.
Center for Integrative Neuroscience, University of Tübingen, 72076 Tübingen, Germany.
Curr Biol. 2016 Oct 24;26(20):2739-2749. doi: 10.1016/j.cub.2016.08.035. Epub 2016 Sep 29.
Sleep is characterized by unique patterns of cortical activity alternating between the stages of slow-wave sleep (SWS) and rapid-eye movement (REM) sleep. How these patterns relate to the balanced activity of excitatory pyramidal cells and inhibitory interneurons in cortical circuits is unknown. We investigated cortical network activity during wakefulness, SWS, and REM sleep globally and locally using in vivo calcium imaging in mice. Wide-field imaging revealed a reduction in pyramidal cell activity during SWS compared with wakefulness and, unexpectedly, a further profound reduction in activity during REM sleep. Two-photon imaging on local circuits showed that this suppression of activity during REM sleep was accompanied by activation of parvalbumin (PV)+ interneurons, but not of somatostatin (SOM)+ interneurons. PV+ interneurons most active during wakefulness were also most active during REM sleep. Our results reveal a sleep-stage-specific regulation of the cortical excitation/inhibition balance, with PV+ interneurons conveying maximum inhibition during REM sleep, which might help shape memories in these networks.
睡眠的特征是在慢波睡眠（SWS）和快速眼动（REM）睡眠阶段之间交替出现独特的皮质活动模式。这些模式如何与皮质回路中兴奋性锥体细胞和抑制性中间神经元的平衡活动相关尚不清楚。我们使用小鼠体内钙成像技术，从全局和局部层面研究了清醒、慢波睡眠和快速眼动睡眠期间的皮质网络活动。广角成像显示，与清醒状态相比，慢波睡眠期间锥体细胞活动减少，而且出乎意料的是，快速眼动睡眠期间活动进一步大幅减少。对局部回路的双光子成像显示，快速眼动睡眠期间这种活动抑制伴随着小白蛋白（PV）阳性中间神经元的激活，但生长抑素（SOM）阳性中间神经元未被激活。在清醒状态下最活跃的PV阳性中间神经元在快速眼动睡眠期间也最活跃。我们的研究结果揭示了皮质兴奋/抑制平衡的睡眠阶段特异性调节，PV阳性中间神经元在快速眼动睡眠期间传递最大抑制，这可能有助于塑造这些网络中的记忆。
