Suppressing sensory arousal is critical for sleep, with deeper sleep requiring stronger sensory suppression. The mechanisms that enable sleeping animals to largely ignore their surroundings are not well understood. We show that the responsiveness of sleeping flies and mice to mechanical vibrations is better suppressed when the diet is protein rich. In flies, we describe a signaling pathway through which information about ingested proteins is conveyed from the gut to the brain to help suppress arousability. Higher protein concentration in the gut leads to increased activity of enteroendocrine cells that release the peptide CCHa1. CCHa1 signals to a small group of dopamine neurons in the brain to modulate their activity; the dopaminergic activity regulates the behavioral responsiveness of animals to vibrations. The CCHa1 pathway and dietary proteins do not influence responsiveness to all sensory inputs, showing that during sleep, different information streams can be gated through independent mechanisms.

抑制感觉唤醒对于睡眠至关重要，更深的睡眠需要更强的感觉抑制。睡眠动物在很大程度上忽视周围环境的机制尚不清楚。我们发现，当饮食富含蛋白质时，熟睡的苍蝇和小鼠对机械振动的反应会得到更好的抑制。在果蝇中，我们描述了一种信号传导途径，通过该途径将有关摄入蛋白质的信息从肠道传递到大脑，以帮助抑制觉醒。肠道中较高的蛋白质浓度会导致肠内分泌细胞释放肽 CCHa1 的活性增加。 CCHa1 向大脑中的一小群多巴胺神经元发出信号，以调节它们的活动；多巴胺能活性调节动物对振动的行为反应。 CCHa1 通路和膳食蛋白质不会影响对所有感觉输入的反应，这表明在睡眠期间，不同的信息流可以通过独立的机制进行门控。