睡眠が認知機能の柔軟性および情動の調節に与える影響の解明

人类的睡眠是循环进行的。深度睡眠在夜间较早的时候更为普遍，而快速眼动睡眠的比例在自然觉醒前的两个周期中会增加。目前还不清楚快速眼动睡眠缺失在影响大脑中控制不健康食物欲望的区域中所起的作用。前额叶皮层（PFC）在通过味道、气味和质地判断食物的适口性方面起着重要作用。此外，肥胖的人在接触高热量食物时，PFC的活动往往会增加。然而，在快速眼动睡眠剥夺后，PFC在调节对美味食物（HPF）的奖励反应中的确切作用尚不清楚。我们选择性地减少小鼠在25-48小时内的快速眼动睡眠，并通过改变谷氨酸门控和伊维菌素门控的氯通道来抑制内侧PFC (mPFC)，从而促进通过超极化感染神经元的神经元抑制。在mPFC失活和REM睡眠缺失的情况下测量HPF消耗。我们发现，与对照动物相比，快速眼动睡眠的缺失增加了HPF的消耗。然而，mPFC失活逆转了快速眼动睡眠缺失对蔗糖消耗的影响，而不影响脂肪消耗。我们的发现首次提供了REM睡眠、mPFC功能和HPF消耗之间的因果关系。换句话说，当我们缺乏睡眠，尤其是缺乏快速眼动睡眠时，内侧前额叶皮层可能在控制我们摄入高蔗糖含量的增重食物的欲望方面发挥直接作用。

Human sleep proceeds in cycles. A greater amount of deep sleep is prevalent earlier in the night, while the proportion of REM sleep increases in the two cycles prior to natural awakening. It is not well understood what role REM sleep loss plays in affecting areas of the brain that control the desire to consume unhealthy foods. The prefrontal cortex (PFC) plays a role in judging the palatability of foods through taste, smell and texture. Moreover, persons who are obese tend to have increased activity in the PFC when exposed to high calorie foods. However, the precise role of the PFC in mediating reward responses to highly palatable foods (HPF) after REM sleep deprivation is unclear. We selectively reduced REM sleep in mice over a 25-48 hr period and chemogenetically inhibited the medial PFC (mPFC) by using an altered glutamate-gated and ivermectin-gated chloride channel that facilitated neuronal inhibition through hyperpolarizing infected neurons. HPF consumption was measured while the mPFC was inactivated and REM sleep loss was induced. We found that REM sleep loss increased HPF consumption compared to control animals. However, mPFC inactivation reversed the effect of REM sleep loss on sucrose consumption without affecting fat consumption. Our findings provide, for the first time, a causal link between REM sleep, mPFC function and HPF consumption. In other words, the medial prefrontal cortex may play a direct role in controlling our desire to consume weight promoting foods, high in sucrose content, when we are lacking sleep, especially REM sleep.