Measurement of GABAergic parameters in the prefrontal cortex in schizophrenia: focus on GABA content, GABA(A) receptor alpha-1 subunit messenger RNA and human GABA transporter-1 (HGAT-1) messenger RNA expression.
The hypothesis that the pathophysiology of schizophrenia may be associated with a dysfunction in GABA transmission in the human prefrontal cortex was investigated. Human post mortem brain tissue from 10 control cases and six cases of schizophrenia were processed for amino acid analysis and for radioactive in situ hybridization. Laminae III and V of three prefrontal cortical areas were examined in detail, namely Brodmann areas 9, 10 and 11. Of these three areas significant changes in GABAergic markers were found only in areas 9 and 10. Of note, a significant decrease in the tissue content of GABA was observed and this was accompanied by a marked increase in the cellular expression of the GABA(A) receptor alpha-1 subunit messenger RNA and a marked decrease in the expression of human GABA transporter-1, the messenger RNA encoding the neuronal GABA transporter protein. The amino acid analysis data provided in this study coupled with the detailed cellular study of several GABAergic markers in the human prefrontal cortex provide direct evidence in support of a disturbance in GABA transmission in the prefrontal cortex, which may be loosely termed "hypofrontality".
Ohnuma
T
T
Department of Psychiatry, Juntendo University School of Medicine, Tokyo, Japan.
Augood
S J
SJ
Arai
H
H
McKenna
P J
PJ
Emson
P C
PC
D000368:Aged; D002352:Carrier Proteins / Q000096:biosynthesis* / Q000235:genetics; D002851:Chromatography, High Pressure Liquid; D015342:DNA Probes; D005260:Female; D050485:GABA Plasma Membrane Transport Proteins; D006801:Humans; D017403:In Situ Hybridization; D008297:Male; D008565:Membrane Proteins / Q000096:biosynthesis* / Q000235:genetics; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000235:genetics; D027361:Organic Anion Transporters; D017397:Prefrontal Cortex / Q000378:metabolism / Q000503:physiopathology*; D012333:RNA, Messenger / Q000096:biosynthesis* / Q000235:genetics; D011963:Receptors, GABA-A / Q000096:biosynthesis* / Q000235:genetics; D012559:Schizophrenia / Q000378:metabolism / Q000503:physiopathology*; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D005680:gamma-Aminobutyric Acid / Q000378:metabolism / Q000502:physiology*
D002352:Carrier Proteins; D015342:DNA Probes; D050485:GABA Plasma Membrane Transport Proteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D027361:Organic Anion Transporters; D012333:RNA, Messenger; D011963:Receptors, GABA-A; D005680:gamma-Aminobutyric Acid