Sleep and Metabolism: Implication of Lateral Hypothalamic Neurons.

During the last decade, optogenetic-based circuit mapping has become one of the most common approaches to systems neuroscience, and amassing studies have expanded our understanding of brain structures causally involved in the regulation of sleep-wake cycles. Recent imaging technologies enable the functional mapping of cellular activity, from population down to single-cell resolution, across a broad repertoire of behaviors and physiological processes, including sleep-wake states. This chapter summarizes experimental evidence implicating hypocretins/orexins, melanin-concentrating hormone, and inhibitory neurons from the lateral hypothalamus (LH) in forming an intricate network involved in regulating sleep and metabolism, including feeding behaviors. It further confirms the dual sleep-metabolic functions of LH cells, and sheds light on a possible mechanism underlying brain plasticity during sleep and metabolic disorders.