title: Assessment of glutamate in striatal subregions in obsessive-compulsive disorder with proton magnetic resonance spectroscopy.
abstract: Glutamatergic signaling abnormalities in cortico-striatal circuits are hypothesized to lead to the repetitive thoughts and behaviors of obsessive-compulsive disorder (OCD). To test this hypothesis, studies have used proton magnetic resonance spectroscopy (1H MRS) to measure glutamatergic compounds in the striatum of individuals with OCD. However, no studies have used methods that could measure glutamate minimally contaminated by glutamine and γ-aminobutyric acid (GABA) in striatal subregions. Therefore, in this study, a proton MRS imaging (1H MRSI) technique with relatively high spatial resolution at 3.0 T was used to measure minimally contaminated glutamate levels in three striatal subregions (i.e., dorsal caudate, dorsal putamen, and ventral striatum) in 15 unmedicated adults with OCD and 16 matched healthy control subjects. No significant group differences in glutamate levels were found in any of the three striatal subregions. In contrast, a study in unmedicated pediatric OCD patients that measured glutamatergic compounds in the dorsal caudate by MRS at 1.5 T found significant elevations. Further studies are warranted to assess whether these discrepant MRS findings are due to differences in subject age or MRS methodology, or potentially are associated with glutamatergic gene variants implicated in OCD.
authors.affiliation: Department of Psychiatry at Columbia University Medical Center, College of Physicians and Surgeons, Columbia University, New York, NY, United States; Division of Clinical Therapeutics at the New York State Psychiatric Institute, New York, NY, United States. Electronic address: simpson@nyspi.columbia.edu.
authors.forename: Helen Blair
authors.initials: HB
authors.lastname: Simpson
authors.affiliation: Department of Psychiatry at Columbia University Medical Center, College of Physicians and Surgeons, Columbia University, New York, NY, United States; Department of Radiology at Columbia University Medical Center, College of Physicians and Surgeons, Columbia University, New York, NY, United States; Division of Translational Imaging at the New York State Psychiatric Institute, New York, NY, United States.
authors.forename: Lawrence S
authors.initials: LS
authors.lastname: Kegeles
authors.affiliation: Division of Clinical Therapeutics at the New York State Psychiatric Institute, New York, NY, United States.
authors.forename: Liane
authors.initials: L
authors.lastname: Hunter
authors.affiliation: Department of Radiology, Weill Cornell Medical College, New York, NY, United States.
authors.forename: Xiangling
authors.initials: X
authors.lastname: Mao
authors.affiliation: Division of Clinical Therapeutics at the New York State Psychiatric Institute, New York, NY, United States.
authors.forename: Page
authors.initials: P
authors.lastname: Van Meter
authors.affiliation: Division of Translational Imaging at the New York State Psychiatric Institute, New York, NY, United States.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Xu
authors.affiliation: Division of Clinical Therapeutics at the New York State Psychiatric Institute, New York, NY, United States.
authors.forename: Marcia B
authors.initials: MB
authors.lastname: Kimeldorf
authors.affiliation: Division of Clinical Therapeutics at the New York State Psychiatric Institute, New York, NY, United States.
authors.forename: Sarah L
authors.initials: SL
authors.lastname: Pearlstein
authors.affiliation: Department of Psychiatry at Columbia University Medical Center, College of Physicians and Surgeons, Columbia University, New York, NY, United States; Division of Translational Imaging at the New York State Psychiatric Institute, New York, NY, United States.
authors.forename: Mark
authors.initials: M
authors.lastname: Slifstein
authors.affiliation: Department of Radiology, Weill Cornell Medical College, New York, NY, United States.
authors.forename: Dikoma C
authors.initials: DC
authors.lastname: Shungu
mesh_terms: D000293:Adolescent; D000328:Adult; D003342:Corpus Striatum / Q000378:metabolism*; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism*; D005973:Glutamine / Q000378:metabolism; D006801:Humans; D008297:Male; D008875:Middle Aged; D009771:Obsessive-Compulsive Disorder / Q000378:metabolism*; D066244:Proton Magnetic Resonance Spectroscopy; D055815:Young Adult; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D005973:Glutamine; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid
keywords: Caudate; Magnetic resonance spectroscopy; OCD; Striatum