title: Effect of a history of major depressive disorder on smoking-induced dopamine release.
abstract: BACKGROUND
  Dopamine (DA) system dysfunction is implicated in the pathophysiology of major depressive disorder (MDD). We sought to determine if cigarette smokers with a history of MDD and current mild depressive symptoms have abnormal smoking-induced DA release (measured indirectly as change in (11)C-raclopride binding potential [BP(ND)]).
  
  
  METHODS
  Fifty-six cigarette smokers either with (n = 10) or without (n = 46) a history of MDD (MDD+ and MDD-, respectively) underwent bolus-plus-continuous-infusion (11)C-raclopride positron emission tomography, during which they smoked a regular cigarette. Presmoking to postsmoking changes in (11)C-raclopride BP(ND) were compared between groups. Also, correlations were determined between change in BP(ND) and depression, anxiety, and withdrawal rating scale scores for the MDD+ group.
  
  
  RESULTS
  The MDD+ group had a significantly greater reduction in (11)C-raclopride BP(ND) (-16.3%) than the MDD- group (-8.4%) (analysis of covariance [ANCOVA], p = .03). Significant negative correlations were found between depression/anxiety and change in (11)C-raclopride BP(ND) (r = -.77, p < .01 and r = -.74, p = .01, respectively).
  
  
  CONCLUSIONS
  MDD+ smokers have greater smoking-induced DA release than MDD- smokers, and higher depression/anxiety levels are associated with greater smoking-induced DA release. These findings support the theory that MDD+ smokers have DA system dysfunction, including heightened smoking-induced DA release.
authors.affiliation: Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, California 90095, USA. abrody@ucla.edu
authors.forename: Arthur L
authors.initials: AL
authors.lastname: Brody
authors.forename: Richard E
authors.initials: RE
authors.lastname: Olmstead
authors.forename: Anna L
authors.initials: AL
authors.lastname: Abrams
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Costello
authors.forename: Aliyah
authors.initials: A
authors.lastname: Khan
authors.forename: Daniel
authors.initials: D
authors.lastname: Kozman
authors.forename: Sanjaya
authors.initials: S
authors.lastname: Saxena
authors.forename: Judah
authors.initials: J
authors.lastname: Farahi
authors.forename: Edythe D
authors.initials: ED
authors.lastname: London
authors.forename: Mark A
authors.initials: MA
authors.lastname: Mandelkern
mesh_terms: D000328:Adult; D000368:Aged; D001007:Anxiety / Q000378:metabolism; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism; D003865:Major Depressive Disorder / Q000150:complications / Q000000981:diagnostic imaging / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D020891:Raclopride / Q000378:metabolism; D011869:Radioligand Assay; D012907:Smoking / Q000378:metabolism*; D013375:Substance Withdrawal Syndrome / Q000378:metabolism; D014029:Tobacco Use Disorder / Q000150:complications / Q000000981:diagnostic imaging / Q000378:metabolism
chemical_list: D020891:Raclopride; D004298:Dopamine