title: Unveiling the role of melatonin MT2 receptors in sleep, anxiety and other neuropsychiatric diseases: a novel target in psychopharmacology.
abstract: BACKGROUND
  Melatonin (MLT) is a pleiotropic neurohormone controlling many physiological processes and whose dysfunction may contribute to several different diseases, such as neurodegenerative diseases, circadian and mood disorders, insomnia, type 2 diabetes and pain. Melatonin is synthesized by the pineal gland during the night and acts through 2 G-protein coupled receptors (GPCRs), MT1 (MEL1a) and MT2 (MEL1b). Although a bulk of research has examined the physiopathological effects of MLT, few studies have investigated the selective role played by MT1 and MT2 receptors. Here we have reviewed current knowledge about the implications of MT2 receptors in brain functions.
  
  
  METHODS
  We searched PubMed, Web of Science, Scopus, Google Scholar and articles' reference lists for studies on MT2 receptor ligands in sleep, anxiety, neuropsychiatric diseases and psychopharmacology, including genetic studies on the MTNR1B gene, which encodes the melatonin MT2 receptor.
  
  
  RESULTS
  These studies demonstrate that MT2 receptors are involved in the pathophysiology and pharmacology of sleep disorders, anxiety, depression, Alzheimer disease and pain and that selective MT2 receptor agonists show hypnotic and anxiolytic properties.
  
  
  CONCLUSIONS
  Studies examining the role of MT2 receptors in psychopharmacology are still limited.
  
  
  CONCLUSIONS
  The development of novel selective MT2 receptor ligands, together with further preclinical in vivo studies, may clarify the role of this receptor in brain function and psychopharmacology. The superfamily of GPCRs has proven to be among the most successful drug targets and, consequently, MT2 receptors have great potential for pioneer drug discovery in the treatment of mental diseases for which limited therapeutic targets are currently available.
authors: Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University and McGill University Health Centre, Montréal, Que., Canada.
authors: Stefano
authors: S
authors: Comai
authors: Neurobiological Psychiatry Unit, Department of Psychiatry, McGill University and McGill University Health Centre, Montréal, Que., Canada.
authors: Gabriella
authors: G
authors: Gobbi
mesh_terms: D000818:Animals; D001008:Anxiety Disorders / Q000188:drug therapy / Q000235:genetics / Q000503:physiopathology*; D001921:Brain / Q000187:drug effects / Q000503:physiopathology; D006801:Humans; D001523:Mental Disorders / Q000188:drug therapy / Q000235:genetics / Q000503:physiopathology*; D011600:Psychopharmacology; D044123:Receptor, Melatonin, MT2 / Q000235:genetics / Q000378:metabolism*; D012893:Sleep Wake Disorders / Q000188:drug therapy / Q000235:genetics / Q000503:physiopathology*
chemical_list: C573871:MTNR1B protein, human; D044123:Receptor, Melatonin, MT2
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