Regulation of Sleep and Wakefulness by Orexin

Orexins known as hypocretins which are neuropeptides exclusively present by neurons in the lateral hypothalamic area. Orexins are known as key modulators of the sleep/wakefulness cycle. The neural networks have revealed integrated roles for orexin neurons in the coordination of emotion & energy homeostasis. orexin also maintain the proper amount of sleep and wakefulness. Billions of cells are present in brain, but there are only 10,000 to 20,000 cells that produce orexin. Cells produce two sorts of orexins, called orexin-A and orexin-B