title: Cortical neurochemistry in euthymic patients with bipolar I disorder.
abstract: OBJECTIVE
  Prefrontal and anterior cingulate cortical regions are assumed to be involved in the pathophysiology of mood regulation. Reduced prefrontal and anterior cingulate function indicated by decreased N-acetyl-aspartate (NAA) levels in patients with bipolar disorder has been reported inconsistently. A positive correlation between lithium serum level and NAA concentrations has been found previously. The aim of this study was to re-investigate prefrontal and anterior cingulate neurochemistry in a sample of euthymic patients with bipolar I disorder.
  
  
  METHODS
  NAA, choline (Cho), creatine (Cr) and myo-inositol (Ins) in left dorsolateral prefrontal cortex and left anterior cingulate cortex were measured in 33 euthymic patients with bipolar I disorder and 29 healthy comparison subjects by using proton magnetic resonance spectroscopy ([(1)H]MRS).
  
  
  RESULTS
  Metabolic ratios did not differ between patients with bipolar I disorder and comparison subjects in prefrontal and anterior cingulate cortex neither in the total sample nor in the pairwise matched sub-sample. We could not observe an association between lithium level and NAA ratios. Lithium treated patients demonstrated unchanged NAA or myo-inositol ratios compared to alternatively treated patients.
  
  
  CONCLUSIONS
  In contrast to prior findings, we could not observe any metabolic alterations in euthymic patients with bipolar disorder.
authors.affiliation: Department of Psychiatry and Psychotherapy, Georg-August-University Goettingen, 37075 Goettingen, Germany. hscherk@uni-goettingen.de
authors.forename: Harald
authors.initials: H
authors.lastname: Scherk
authors.forename: Martin
authors.initials: M
authors.lastname: Backens
authors.forename: Thomas
authors.initials: T
authors.lastname: Schneider-Axmann
authors.forename: Juliana
authors.initials: J
authors.lastname: Usher
authors.forename: Claudia
authors.initials: C
authors.lastname: Kemmer
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Reith
authors.forename: Peter
authors.initials: P
authors.lastname: Falkai
authors.forename: Oliver
authors.initials: O
authors.lastname: Gruber
mesh_terms: D000328:Adult; D000339:Affect / Q000502:physiology*; D018692:Antimanic Agents / Q000493:pharmacokinetics / Q000627:therapeutic use; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D001714:Bipolar Disorder / Q000175:diagnosis / Q000188:drug therapy / Q000503:physiopathology* / Q000523:psychology; D002794:Choline / Q000378:metabolism*; D003401:Creatine / Q000378:metabolism*; D004292:Dominance, Cerebral / Q000502:physiology; D005260:Female; D006179:Gyrus Cinguli / Q000187:drug effects / Q000503:physiopathology*; D006801:Humans; D007294:Inositol / Q000378:metabolism*; D016651:Lithium Carbonate / Q000493:pharmacokinetics / Q000627:therapeutic use; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D016555:Matched-Pair Analysis; D008875:Middle Aged; D017397:Prefrontal Cortex / Q000187:drug effects / Q000503:physiopathology*; D012016:Reference Values; D012737:Sex Factors; D055815:Young Adult
chemical_list: D018692:Antimanic Agents; D016651:Lithium Carbonate; D001224:Aspartic Acid; D007294:Inositol; C000179:N-acetylaspartate; D003401:Creatine; D002794:Choline