Article

GABAA Receptor Downregulation in Brains of Subjects with Autism

School of Medicine, University of Minnesota Department of Neuroscience Minneapolis MN USA
Journal of Autism and Developmental Disorders (Impact Factor: 3.34). 02/2008; 39(2):223-230. DOI: 10.1007/s10803-008-0646-7

ABSTRACT Gamma-aminobutyric acid A (GABAA) receptors are ligand-gated ion channels responsible for mediation of fast inhibitory action of GABA in the brain. Preliminary
reports have demonstrated altered expression of GABA receptors in the brains of subjects with autism suggesting GABA/glutamate
system dysregulation. We investigated the expression of four GABAA receptor subunits and observed significant reductions in GABRA1, GABRA2, GABRA3, and GABRB3 in parietal cortex (Brodmann’s
Area 40 (BA40)), while GABRA1 and GABRB3 were significantly altered in cerebellum, and GABRA1 was significantly altered in
superior frontal cortex (BA9). The presence of seizure disorder did not have a significant impact on GABAA receptor subunit expression in the three brain areas. Our results demonstrate that GABAA receptors are reduced in three brain regions that have previously been implicated in the pathogenesis of autism, suggesting
widespread GABAergic dysfunction in the brains of subjects with autism.

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