title: Multinuclear magnetic resonance spectroscopy studies of brain purines in major depression.
abstract: OBJECTIVE
  Studies of depressed adults have shown abnormalities in cerebral energy metabolism, as noted by low brain levels of nucleoside triphosphate (NTP), which primarily represents adenosine triphosphate (ATP). This study was undertaken to determine whether proton magnetic resonance spectroscopy (1H MRS) measures of the low-field purine resonance, which arises primarily from adenosine phosphates, can be used to assess abnormalities in cerebral purine metabolism in depressed adults.
  
  
  METHODS
  Data from 1H MRS and phosphorus-31 (31P) MRS were acquired for depressed and nondepressed comparison subjects. Intensities of the purine resonance, by 1H MRS (7.5-8.5 ppm), and of NTP, by 31P MRS, were determined.
  
  
  RESULTS
  Purine resonance intensities did not differ on average between depressed patients and comparison subjects. However, purine levels were approximately 30% lower in female depressed subjects who subsequently responded to fluoxetine treatment than in those who did not respond. Beta-NTP was lower by 21% in responders than in nonresponders and was correlated with purine levels for the depressed subjects.
  
  
  CONCLUSIONS
  Brain purine levels are low in female depressed patients who respond to treatment with fluoxetine, suggesting that response to treatment might be predicted by using 1H MRS. These observations also suggest that agents that increase brain adenosine levels may have antidepressant efficacy.
authors.affiliation: Brain Imaging Center, McLean Hospital, Belmont, MA 02478, USA. perry@mclean.harvard.edu
authors.forename: P F
authors.initials: PF
authors.lastname: Renshaw
authors.forename: A M
authors.initials: AM
authors.lastname: Parow
authors.forename: F
authors.initials: F
authors.lastname: Hirashima
authors.forename: Y
authors.initials: Y
authors.lastname: Ke
authors.forename: C M
authors.initials: CM
authors.lastname: Moore
authors.forename: B de B
authors.initials: Bde B
authors.lastname: Frederick
authors.forename: M
authors.initials: M
authors.lastname: Fava
authors.forename: J
authors.initials: J
authors.lastname: Hennen
authors.forename: B M
authors.initials: BM
authors.lastname: Cohen
mesh_terms: D000255:Adenosine Triphosphate / Q000031:analogs & derivatives* / Q000378:metabolism; D000328:Adult; D001479:Basal Ganglia / Q000187:drug effects / Q000503:physiopathology; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D004734:Energy Metabolism / Q000187:drug effects / Q000502:physiology; D005260:Female; D005473:Fluoxetine / Q000627:therapeutic use; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008875:Middle Aged; D011687:Purines / Q000378:metabolism*; D012016:Reference Values; D013873:Thionucleotides / Q000378:metabolism
chemical_list: D011687:Purines; D013873:Thionucleotides; D005473:Fluoxetine; C022570:adenosine 5'-O-(2-thiotriphosphate); D000255:Adenosine Triphosphate