Cellular and Molecular Neurobiology

, Volume 30, Issue 4, pp 599–606

Decreased GABAA Receptors Functional Regulation in the Cerebral Cortex and Brainstem of Hypoxic Neonatal Rats: Effect of Glucose and Oxygen Supplementation

Original Research


Hypoxia in neonates can lead to biochemical and molecular alterations mediated through changes in neurotransmitters resulting in permanent damage to brain. In this study, we evaluated the changes in the receptor status of GABAA in the cerebral cortex and brainstem of hypoxic neonatal rats and hypoxic rats supplemented with glucose and oxygen using binding assays and gene expression of GABAAα1 and GABAAγ5. In the cerebral cortex and brainstem of hypoxic neonatal rats, a significant decrease in GABAA receptors was observed, which accounts for the respiratory inhibition. Hypoxic rats supplemented with glucose alone and with glucose and oxygen showed a reversal of the GABAA receptors, andGABAAα1 and GABAAγ5 gene expression to control. Glucose acts as an immediate energy source thereby reducing the ATP-depletion-induced increase in GABA and oxygenation, which helps in encountering anoxia. Resuscitation with oxygen alone was less effective in reversing the receptor alterations. Thus, the results of this study suggest that reduction in the GABAA receptors functional regulation during hypoxia plays an important role in mediating the brain damage. Glucose alone and glucose and oxygen supplementation to hypoxic neonatal rats helps in protecting the brain from severe hypoxic damage.


GABAA Hypoxia Cerebral cortex Brainstem Bicuculline 


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Molecular Neurobiology and Cell Biology Unit, Centre for Neuroscience, Department of BiotechnologyCochin University of Science and TechnologyCochinIndia

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