title: Sex differences in diencephalon serotonin transporter availability in major depression.
abstract: BACKGROUND
  Major depression is more prevalent in women than men. The present study evaluated if previous findings that demonstrated decreased 5-hydroxytryptamine (5-HT) transporter availability in depressed patients would be confirmed in a larger sample and also evaluated sex differences.
  
  
  METHODS
  Depressed (n = 32) and healthy subjects (n = 32), including 16 pairs of women and men, participated in an iodine-123-2 beta-carbomethoxy-3beta-(4-iodophenyltropane) ([(123)I]beta-CIT) single photon emission computed tomography (SPECT) and a magnetic resonance imaging (MRI) scan. Participants were administered [(123)I]beta-CIT (225.7 +/- 3.7 MBq) and imaged 23.0 +/- 1.6 hours later. Statistical analyses included analysis of variance and a regression analysis of the main and interactive effects of age, sex, and depression.
  
  
  RESULTS
  Overall, depressed patients demonstrated 12% lower diencephalon and no change in striatal or brainstem [(123)I]beta-CIT uptake. Significant age by sex, sex by depression, and age by sex by depression interactions were noted due to 22% lower diencephalon [(123)I]beta-CIT uptake in depressed women compared with less than a 1% decrease in depressed men.
  
  
  CONCLUSIONS
  As observed previously, diencephalon 5-HT transporter availability is decreased in depressed patients. However, the decrease appears to be sex-specific and age-dependent. These findings suggest that serotonergic mechanisms mediating depressed mood differ between men and women in an age-dependent manner and may explain why young women respond better to treatment with selective serotonin reuptake inhibitor (SSRI) antidepressants.
authors.affiliation: Department of Psychiatry, Yale University School of Medicine and West Haven VA Connecticut Health Care System, CT 06516, USA. julie.staley@yale.edu
authors.forename: Julie K
authors.initials: JK
authors.lastname: Staley
authors.forename: Gerard
authors.initials: G
authors.lastname: Sanacora
authors.forename: Gilles
authors.initials: G
authors.lastname: Tamagnan
authors.forename: Paul K
authors.initials: PK
authors.lastname: Maciejewski
authors.forename: Robert T
authors.initials: RT
authors.lastname: Malison
authors.forename: Robert M
authors.initials: RM
authors.lastname: Berman
authors.forename: Meena
authors.initials: M
authors.lastname: Vythilingam
authors.forename: Akira
authors.initials: A
authors.lastname: Kugaya
authors.forename: Ronald M
authors.initials: RM
authors.lastname: Baldwin
authors.forename: John P
authors.initials: JP
authors.lastname: Seibyl
authors.forename: Dennis
authors.initials: D
authors.lastname: Charney
authors.forename: Robert B
authors.initials: RB
authors.lastname: Innis
mesh_terms: D000328:Adult; D001931:Brain Mapping; D016022:Case-Control Studies; D003042:Cocaine / Q000031:analogs & derivatives / Q000493:pharmacokinetics; D003865:Major Depressive Disorder / Q000000981:diagnostic imaging / Q000378:metabolism*; D004027:Diencephalon / Q000000981:diagnostic imaging / Q000378:metabolism*; D050483:Dopamine Plasma Membrane Transport Proteins / Q000378:metabolism; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D007456:Iodine Isotopes / Q000493:pharmacokinetics; D008297:Male; D008875:Middle Aged; D050486:Serotonin Plasma Membrane Transport Proteins / Q000378:metabolism*; D012727:Sex Characteristics; D013223:Statistics as Topic; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins; D007456:Iodine Isotopes; D050486:Serotonin Plasma Membrane Transport Proteins; C069723:2beta-carbomethoxy-3beta-(4-iodophenyl)tropane; D003042:Cocaine