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Polygraphic Recording Procedure for Measuring Sleep in Mice
Published on: January 26, 2016
The role of hypocretins (orexins) in sleep regulation and narcolepsy
Shahrad Taheri1, Jamie M Zeitzer, Emmanuel Mignot
1Stanford University Center for Narcolepsy, 701 Welch Road B, Basement, Palo Alto, California 94304-5742, USA. staheri@stanford.edu
Abstract:
The hypocretins (orexins) are two novel neuropeptides (Hcrt-1 and Hcrt-2), derived from the same precursor gene, that are synthesized by neurons located exclusively in the lateral, posterior, and perifornical hypothalamus. Hypocretin-containing neurons have widespread projections throughout the CNS with particularly dense excitatory projections to monoaminergic centers such as the noradrenergic locus coeruleus, histaminergic tuberomammillary nucleus, serotoninergic raphe nucleus, and dopaminergic ventral tegmental area. The hypocretins were originally believed to be primarily important in the regulation of appetite; however, a major function emerging from research on these neuropeptides is the regulation of sleep and wakefulness. Deficiency in hypocretin neurotransmission results in the sleep disorder narcolepsy in mice, dogs, and humans. The hypocretins are also uniquely positioned to link sleep, appetite, and neuroendocrine control. The aim of this review is to describe and discuss the current knowledge regarding the hypocretin neurotransmitter system in narcolepsy and normal sleep.
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