Molecular Neurobiology

, Volume 43, Issue 2, pp 97–106

The Depolarizing Action of GABA Controls Early Network Activity in the Developing Hippocampus

Authors

    • Neurobiology Sector and IIT UnitInternational School for Advanced Studies (SISSA)
  • Marilena Griguoli
    • Neurobiology Sector and IIT UnitInternational School for Advanced Studies (SISSA)
  • Victoria Safiulina
    • Neurobiology Sector and IIT UnitInternational School for Advanced Studies (SISSA)
  • Laura Lagostena
    • Neurobiology Sector and IIT UnitInternational School for Advanced Studies (SISSA)
Article

DOI: 10.1007/s12035-010-8147-z

Cite this article as:
Cherubini, E., Griguoli, M., Safiulina, V. et al. Mol Neurobiol (2011) 43: 97. doi:10.1007/s12035-010-8147-z

Abstract

Early in postnatal life γ-aminobutyric acid (GABA), the primary inhibitory transmitter in adults, excites targeted neurons by an outwardly directed flux of chloride which results from the unbalance between the cation–chloride cotransporters NKCC1 and KCC2, involved in chloride uptake and extrusion, respectively. This effect contributes to generate synchronized network activity or giant depolarizing potentials (GDPs) in the developing hippocampus. Here, we review some recent data concerning the mechanisms by which GDPs are generated and their functional role in enhancing synaptic efficacy at poorly developed GABAergic and glutamatergic synapses. In adulthood, reshaping neuronal circuits due to changes in chloride homeostasis and to the shift of GABA from hyperpolarizing to depolarizing, has been implicated in several neurological disorders, including epilepsy. Evidence has been recently provided that in chronically nerve growth factor-deprived mice expressing a progressive age-dependent neurodegenerative pathology resembling that observed in patients with Alzheimer’s disease, the reduced expression of mRNA encoding for the Kcc2 gene and the depolarizing action of GABA lead to the reorganization of the neuronal hippocampal network. This may represent a novel mechanism by which GABAergic signaling counterbalances the loss of synaptic activity in neurodegenerative diseases.

Keywords

Depolarizing action of GABADevelopmentCation–chloride cotransportersSynaptic efficacyCorrelated network activityGDPsNGFNeurodegeneration

Copyright information

© Springer Science+Business Media, LLC 2010