title: Melatonin in mood disorders.
abstract: The cyclic nature of depressive illness, the diurnal variations in its symptomatology and the existence of disturbed sleep-wake and core body temperature rhythms, all suggest that dysfunction of the circadian time keeping system may underlie the pathophysiology of depression. As a rhythm-regulating factor, the study of melatonin in various depressive illnesses has gained attention. Melatonin can be both a 'state marker' and a 'trait marker' of mood disorders. Measurement of melatonin either in saliva or plasma, or of its main metabolite 6-sulfatoxymelatonin in urine, have documented significant alterations in melatonin secretion in depressive patients during the acute phase of illness. Not only the levels but also the timing of melatonin secretion is altered in bipolar affective disorder and in patients with seasonal affective disorder (SAD). A phase delay of melatonin secretion takes place in SAD, as well as changes in the onset, duration and offset of melatonin secretion. Bright light treatment, that suppresses melatonin production, is effective in treating bipolar affective disorder and SAD, winter type. This review discusses the role of melatonin in the pathophysiology of bipolar disorder and SAD.
authors.affiliation: Department of Physiology, School of Medical Sciences, University Sains Malaysia, Kubang Kerian, Kota Bharu, Kelantan.
authors.forename: Venkataramanujan
authors.initials: V
authors.lastname: Srinivasan
authors.forename: Marcel
authors.initials: M
authors.lastname: Smits
authors.forename: Warren
authors.initials: W
authors.lastname: Spence
authors.forename: Alan D
authors.initials: AD
authors.lastname: Lowe
authors.forename: Leonid
authors.initials: L
authors.lastname: Kayumov
authors.forename: Seithikurippu R
authors.initials: SR
authors.lastname: Pandi-Perumal
authors.forename: Barbara
authors.initials: B
authors.lastname: Parry
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Cardinali
mesh_terms: D000928:Antidepressive Agents / Q000627:therapeutic use; D015415:Biomarkers / Q000097:blood; D001714:Bipolar Disorder / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology*; D002940:Circadian Rhythm / Q000187:drug effects / Q000502:physiology; D003866:Depressive Disorder / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology*; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology; D006801:Humans; D008550:Melatonin / Q000097:blood* / Q000627:therapeutic use; D010789:Phototherapy; D016574:Seasonal Affective Disorder / Q000175:diagnosis / Q000503:physiopathology; D020178:Sleep Disorders, Circadian Rhythm / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology; D016896:Treatment Outcome
chemical_list: D000928:Antidepressive Agents; D015415:Biomarkers; D008550:Melatonin