title: The brain's master circadian clock: implications and opportunities for therapy of sleep disorders.
abstract: The suprachiasmatic nuclei (SCN) residing in the anterior hypothalamus maintains a near-24-h rhythm of electrical activity, even in the absence of environmental cues. This circadian rhythm is generated by intrinsic molecular mechanisms in the neurons of the SCN; however, the circadian clock is modulated by a wide variety of influences, including glutamate and pituitary adenylate cyclase-activating peptide (PACAP) from the retinohypothalamic tract, melatonin from the pineal gland, and neuropeptide Y from the intergeniculate leaflet. By virtue of these and other inputs, the SCN responds to environmental cues such as light, social and physical activities. In turn, the SCN controls or influences a wide variety of physiologic and behavioral functions, including attention, endocrine cycles, body temperature, melatonin secretion, and the sleep-wake cycle. Regulation of the sleep-wake cycle by the SCN has important implications for development of therapies for sleep disorders, including those involving desynchronization of circadian rhythms and insomnia.
authors.affiliation: Department of Neurology, Northwestern University School of Medicine, 710 N. Lake Shore Dr, 11th Floor, Chicago, IL 60611, USA. p-zee@northwestern.edu
authors.forename: Phyllis C
authors.initials: PC
authors.lastname: Zee
authors.forename: Prasanth
authors.initials: P
authors.lastname: Manthena
mesh_terms: D000975:Antioxidants / Q000627:therapeutic use; D001831:Body Temperature; D002940:Circadian Rhythm / Q000502:physiology*; D006801:Humans; D007031:Hypothalamus / Q000502:physiology*; D008550:Melatonin / Q000502:physiology / Q000627:therapeutic use; D010789:Phototherapy / Q000379:methods*; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide / Q000502:physiology; D012165:Retinal Ganglion Cells / Q000502:physiology; D020178:Sleep Disorders, Circadian Rhythm / Q000503:physiopathology; D012893:Sleep Wake Disorders / Q000188:drug therapy / Q000628:therapy*; D014851:Wakefulness / Q000502:physiology
chemical_list: D000975:Antioxidants; D051219:Pituitary Adenylate Cyclase-Activating Polypeptide; D008550:Melatonin