title: Alteration of plasma glutamate and glutamine levels in children with high-functioning autism.
abstract: BACKGROUND
  It has recently been hypothesized that hyperglutamatergia in the brain is involved in the pathophysiology of autism. However, there is no conclusive evidence of the validity of this hypothesis. As peripheral glutamate/glutamine levels have been reported to be correlated with those of the central nervous system, the authors examined whether the levels of 25 amino acids, including glutamate and glutamine, in the platelet-poor plasma of drug-naïve, male children with high-functioning autism (HFA) would be altered compared with those of normal controls.
  
  
  RESULTS
  Plasma levels of 25 amino acids in male children (N = 23) with HFA and normally developed healthy male controls (N = 22) were determined using high-performance liquid chromatography. Multiple testing was allowed for in the analyses. Compared with the normal control group, the HFA group had higher levels of plasma glutamate and lower levels of plasma glutamine. No significant group difference was found in the remaining 23 amino acids. The effect size (Cohen's d) for glutamate and glutamine was large: 1.13 and 1.36, respectively. Using discriminant analysis with logistic regression, the two values of plasma glutamate and glutamine were shown to well-differentiate the HFA group from the control group; the rate of correct classification was 91%.
  
  
  CONCLUSIONS
  The present study suggests that plasma glutamate and glutamine levels can serve as a diagnostic tool for the early detection of autism, especially normal IQ autism. These findings indicate that glutamatergic abnormalities in the brain may be associated with the pathobiology of autism.
authors: Department of Psychiatry and Neurology, Hamamatsu University School of Medicine, Hamamatsu, Japan.
authors: Chie
authors: C
authors: Shimmura
authors: Shiro
authors: S
authors: Suda
authors: Kenji J
authors: KJ
authors: Tsuchiya
authors: Kenji
authors: K
authors: Hashimoto
authors: Koji
authors: K
authors: Ohno
authors: Hideo
authors: H
authors: Matsuzaki
authors: Keiko
authors: K
authors: Iwata
authors: Kaori
authors: K
authors: Matsumoto
authors: Tomoyasu
authors: T
authors: Wakuda
authors: Yosuke
authors: Y
authors: Kameno
authors: Katsuaki
authors: K
authors: Suzuki
authors: Masatsugu
authors: M
authors: Tsujii
authors: Kazuhiko
authors: K
authors: Nakamura
authors: Nori
authors: N
authors: Takei
authors: Norio
authors: N
authors: Mori
mesh_terms: D000293:Adolescent; D001321:Autistic Disorder / Q000097:blood* / Q000175:diagnosis; D016022:Case-Control Studies; D002648:Child; D002851:Chromatography, High Pressure Liquid; D016002:Discriminant Analysis; D018698:Glutamic Acid / Q000097:blood*; D005973:Glutamine / Q000097:blood*; D006801:Humans; D008297:Male
chemical_list: D005973:Glutamine; D018698:Glutamic Acid