title: Increased GABA levels in medial prefrontal cortex of young adults with narcolepsy.
abstract: OBJECTIVE
  To explore absolute concentrations of brain metabolites including gamma amino-butyric acid (GABA) in the medial prefrontal cortex and basal ganglia of young adults with narcolepsy.
  
  
  METHODS
  Proton magnetic resonance (MR) spectroscopy centered on the medial prefrontal cortex and the basal ganglia was acquired. The absolute concentrations of brain metabolites including GABA and glutamate were assessed and compared between narcoleptic patients and healthy comparison subjects.
  
  
  METHODS
  Sleep and Chronobiology Center at Seoul National University Hospital; A high strength 3.0 Tesla MR scanner in the Department of Radiology at Seoul National University Hospital.
  
  
  METHODS
  Seventeen young adults with a sole diagnosis of HLA DQB1 0602 positive narcolepsy with cataplexy (25.1 +/- 4.6 years old) and 17 healthy comparison subjects (26.8 +/- 4.8 years old).
  
  
  METHODS
  N/A.
  
  
  RESULTS
  Relative to comparison subjects, narcoleptic patients had higher GABA concentration in the medial prefrontal cortex (t = 4.10, P <0.001). Narcoleptic patients with nocturnal sleep disturbance had higher GABA concentration in the medial prefrontal cortex than those without nocturnal sleep disturbance (t = 2.45, P = 0.03), but had lower GABA concentration than comparison subjects (t = 2.30, P = 0.03).
  
  
  CONCLUSIONS
  The current study reports that young adults with narcolepsy had a higher GABA concentration in the medial prefrontal cortex, which was more prominent in patients without nocturnal sleep disturbance. Our findings suggest that the medial prefrontal GABA level may be increased in narcolepsy, and the increased medial prefrontal GABA might be a compensatory mechanism to reduce nocturnal sleep disturbances in narcolepsy.
authors: Department of Psychiatry, Gachon University of Medicine and Science, Incheon, South Korea.
authors: Seog Ju
authors: SJ
authors: Kim
authors: In Kyoon
authors: IK
authors: Lyoo
authors: Yujin S
authors: YS
authors: Lee
authors: Young Hoon
authors: YH
authors: Sung
authors: Hengjun J
authors: HJ
authors: Kim
authors: Jihyun H
authors: JH
authors: Kim
authors: Kye Hyun
authors: KH
authors: Kim
authors: Do-Un
authors: DU
authors: Jeong
mesh_terms: D000328:Adult; D001479:Basal Ganglia / Q000503:physiopathology; D002385:Cataplexy / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology; D005260:Female; D005838:Genotype; D018698:Glutamic Acid / Q000378:metabolism; D006683:HLA-DQ Antigens / Q000235:genetics; D059866:HLA-DQ beta-Chains; D006801:Humans; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics; D009290:Narcolepsy / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology*; D017397:Prefrontal Cortex / Q000503:physiopathology*; D012016:Reference Values; D020178:Sleep Disorders, Circadian Rhythm / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
chemical_list: D006683:HLA-DQ Antigens; D059866:HLA-DQ beta-Chains; C069051:HLA-DQB1 antigen; D008562:Membrane Glycoproteins; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid