Takahashi K, Lin J-S, Sakai K
INSERM U628, Lyon, F-69373, France and Claude Bernard University Lyon 1, 8 Avenue Rockefeller, Lyon Cedex 08, F-69373, France.
Neuroscience. 2009 Jun 16;161(1):269-92. doi: 10.1016/j.neuroscience.2009.02.075. Epub 2009 Mar 12.
We recorded 872 single units across the complete sleep-waking cycle in the mouse preoptic area (POA) and basal forebrain (BFB), which are deeply involved in the regulation of sleep and wakefulness (W). Of these, 552 were sleep-active, 96 were waking-active, 106 were active during both waking and paradoxical sleep (PS), and the remaining 118 were state-indifferent. Among the 872, we distinguished slow-wave sleep (SWS)-specific, SWS/PS-specific, PS-specific, W-specific, and W/PS-specific neurons, the last group being further divided into specific tonic type I slow (TI-Ss) and specific tonic type I rapid (TI-Rs) both discharging specifically in association with cortical activation during both W and PS. Both the SWS/PS-specific and PS-specific neurons were distributed throughout a wide region of the POA and BFB, whereas the SWS-specific neurons were mainly located in the middle and ventral half of the POA and adjacent BFB, as were the W-specific and W/PS-specific neurons. At the transition from waking to sleep, the majority of SWS-specific and all SWS/PS-specific neurons fired after the onset of cortical synchronization (deactivation), whereas all W-specific and W/PS-specific neurons showed a significant decrease in firing rate >0.5 s before the onset. At the transition from SWS to W, the sleep-specific neurons showed a significant decrease in firing rate 0.1 s before the onset of cortical activation, while the W-specific and W/PS-specific neurons fired >0.5 s before the onset. TI-Ss neurons were characterized by a triphasic broad action potential, slow single isolated firing, and an antidromic response to cortical stimulation, whereas TI-Rs neurons were characterized by a narrow action potential and high frequency burst discharge in association with theta waves in PS. These data suggest that the forebrain sleep/waking switch is regulated by opposing activities of sleep-promoting (SWS-specific and SWS/PS-specific) and waking-promoting (W-specific and W/PS-specific) neurons, that the initiation of sleep is caused by decreased activity of the waking-promoting neurons (disfacilitation), and that the W/PS-specific neurons are deeply involved in the processes of cortical activation/deactivation.
我们在小鼠视前区（POA）和基底前脑（BFB）的整个睡眠 - 觉醒周期中记录了872个单神经元，这些区域深度参与睡眠和觉醒（W）的调节。其中，552个在睡眠时活跃，96个在觉醒时活跃，106个在觉醒和异相睡眠（PS）期间均活跃，其余118个对睡眠 - 觉醒状态无偏好。在这872个神经元中，我们区分出慢波睡眠（SWS）特异性、SWS/PS特异性、PS特异性、W特异性以及W/PS特异性神经元，最后一组又进一步分为特定的紧张性I型慢放电（TI - Ss）和特定的紧张性I型快放电（TI - Rs）神经元，它们在W和PS期间均与皮质激活相关联而特异性放电。SWS/PS特异性和PS特异性神经元分布在POA和BFB的广泛区域，而SWS特异性神经元主要位于POA的中腹侧半部以及相邻的BFB，W特异性和W/PS特异性神经元也是如此。在从觉醒向睡眠转变时，大多数SWS特异性和所有SWS/PS特异性神经元在皮质同步化（失活）开始后放电，而所有W特异性和W/PS特异性神经元在开始前>0.5秒放电频率显著降低。在从SWS向W转变时，睡眠特异性神经元在皮质激活开始前0.1秒放电频率显著降低，而W特异性和W/PS特异性神经元在开始前>0.5秒放电。TI - Ss神经元的特征是具有三相宽动作电位、缓慢的单个孤立放电以及对皮质刺激的逆行反应，而TI - Rs神经元的特征是具有窄动作电位以及在PS期间与θ波相关的高频爆发性放电。这些数据表明，前脑睡眠/觉醒转换受促进睡眠（SWS特异性和SWS/PS特异性）和促进觉醒（W特异性和W/PS特异性）神经元的相反活动调节，睡眠的起始是由促进觉醒神经元的活动降低（去易化）引起的，并且W/PS特异性神经元深度参与皮质激活/失活过程。
