Hypothalamic neuropeptides implicated in the regulation of sleep/wakefulness States.
Summary of "Hypothalamic neuropeptides implicated in the regulation of sleep/wakefulness States."
Abstract Several neuropeptides, including galanin, orexin, melanin-concentrating hormone (MCH), urocortin-2, pituitary adenylate cyclase activating protein, and vasoactive intestinal peptide, have been implicated in the regulation of sleep/wakefulness states. In particular, neuropeptides produced in the hypothalamus, including galanin, orexin, and MCH, have been shown to play crucial roles. Galanin is localized to the prepotic area of the hypothalamus and is likely to be involved in the promotion and maintenance of sleep. MCH, which is expressed by neurons in the lateral hypothalamic area (LHA), seems to be implicated in rapid eye movement sleep regulation. Orexins are also localized in the LHA and have been established as one of the most important factors in the regulation of sleep/wakefulness states. A series of studies have suggested that orexin deficiency causes narcolepsy in humans and other mammalian species, highlighting the roles of this hypothalamic neuropeptide in the regulation of sleep and wakefulness. Studies of efferent and afferent systems of orexin-producing neurons have shown that the orexin neuronal system has close interactions with the systems that regulate emotion, energy homeostasis, reward, and arousal. These observations suggest that orexin neurons are involved in sensing the body's external and internal environments and regulate vigilance states accordingly.
Department of Molecular Neuroscience & Integrative Physiology, Faculty of Medicine, Kanazawa University.
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Name: Brain and nerve = Shinkei kenkyÅ« no shinpo
Medical and Biotech [MESH] Definitions
Sleep-wake Transition Disorders
Parasomnias characterized by behavioral abnormalities that occur during the transition between wakefulness and sleep (or between sleep and wakefulness).
Periods of sleep manifested by changes in EEG activity and certain behavioral correlates; includes Stage 1: sleep onset, drowsy sleep; Stage 2: light sleep; Stages 3 and 4: delta sleep, light sleep, deep sleep, telencephalic sleep.
A biogenic amine that is found in animals and plants. In mammals, melatonin is produced by the PINEAL GLAND. Its secretion increases in darkness and decreases during exposure to light. Melatonin is implicated in the regulation of SLEEP, mood, and REPRODUCTION. Melatonin is also an effective antioxidant.
Sleep Disorders, Intrinsic
Dyssomnias (i.e., insomnias or hypersomnias) associated with dysfunction of internal sleep mechanisms or secondary to a sleep-related medical disorder (e.g., sleep apnea, post-traumatic sleep disorders, etc.). (From Thorpy, Sleep Disorders Medicine, 1994, p187)
Movements or behaviors associated with sleep, sleep stages, or partial arousals from sleep that may impair sleep maintenance. Parasomnias are generally divided into four groups: arousal disorders, sleep-wake transition disorders, parasomnias of REM sleep, and nonspecific parasomnias. (From Thorpy, Sleep Disorders Medicine, 1994, p191)
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