title: Melatonin MT1 and MT2 receptor expression in Parkinson's disease.
abstract: BACKGROUND
  Idiopathic Parkinson disease (PD) is a multi-system disorder with a multifactorial etiology and diverse clinical phenotype. Selective, regional dopaminergic neuronal degeneration in the substantia nigra and other CNS areas including the amygdala are observed in all patients. Apoptotic mechanisms resulting from oxidative stress and mitochondrial dysfunction have been implicated in the pathogenesis of the disease. Although the role of melatonin, a potent endogenous antioxidant, has been highlighted in PD there is no data on the expression of melatonin receptors in affected CNS regions.
  
  
  METHODS
  We conducted an RT-PCR-based study to determine the MT1 and MT2 receptors expression in whole brain post-mortem tissue from the amygdala and substantia nigra of well-characterized PD and control subjects.
  
  
  RESULTS
  PD cases showed a statistically significant decrease of MT1 receptor expression in both substantia nigra (FC=5.11; p<0.05) and the amygdala (FC=3.11; p<0.001) versus normal controls. The expression of MT2 receptor expression was also decreased in both substantia nigra (FC=3.90; p<0.0001) and the amygdala (FC=1.91; p<0.001) versus normal controls.
  
  
  CONCLUSIONS
  The results demonstrate a down-regulation of melatonin receptors in regions affected by PD, suggesting their possible involvement in the disease process. Future studies are needed to elucidate the role of melatonin and its receptors in the treatment/pathogenesis of PD.
authors.affiliation: Department of Neurology, University of Miami, Miller School of Medicine, Miami, FL, USA.
authors.forename: Nikhil
authors.initials: N
authors.lastname: Adi
authors.forename: Deborah C
authors.initials: DC
authors.lastname: Mash
authors.forename: Yousuf
authors.initials: Y
authors.lastname: Ali
authors.forename: Carlos
authors.initials: C
authors.lastname: Singer
authors.forename: Lina
authors.initials: L
authors.lastname: Shehadeh
authors.forename: Spyridon
authors.initials: S
authors.lastname: Papapetropoulos
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000679:Amygdala / Q000378:metabolism / Q000473:pathology; D016022:Case-Control Studies; D015331:Cohort Studies; D015536:Down-Regulation; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D010300:Parkinson Disease / Q000235:genetics* / Q000378:metabolism* / Q000473:pathology; D044122:Receptor, Melatonin, MT1 / Q000235:genetics* / Q000378:metabolism*; D044123:Receptor, Melatonin, MT2 / Q000235:genetics* / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013378:Substantia Nigra / Q000378:metabolism / Q000473:pathology
chemical_list: D044122:Receptor, Melatonin, MT1; D044123:Receptor, Melatonin, MT2