Excitatory GABAergic activation of cortical dividing glial cells

Cereb Cortex. 2009 Sep;19(9):2181-95. doi: 10.1093/cercor/bhn238. Epub 2009 Jan 8.

Abstract

Adult neocortex contains dividing satellite glia population even though their characteristics and functions have still remained unknown. Nestin(+)/NG2(+) cells as major fraction of dividing glial cells express bicuculline-sensitive gamma-aminobutyric acid A (GABA(A)) receptors and receive GABAergic inputs. Due to their high [Cl(-)](i), GABAergic activation depolarized the cells and then induced Ca(2+) influx into them. To assess an effect of this GABAergic excitation, we looked for the expression of neurotrophic factors. Among them, we detected the expression of brain-derived neurotrophic factor (BDNF) on the cells. The level of BDNF expression was elevated after cortical ischemia, and this elevation was blocked by bumetanide, an inhibitor for NKCC1 that blocks the GABAergic depolarization. Furthermore, performing a modified adhesive removal test, we observed that the treatment of bumetanide significantly attenuated the recovery in somatosensory dysfunction. Our results may shed a light on satellite glia population in the cortex and imply their roles in the functional recovery after ischemic injuries.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Action Potentials / physiology*
  • Animals
  • Brain-Derived Neurotrophic Factor / metabolism*
  • Cerebral Cortex / physiology*
  • Excitatory Postsynaptic Potentials / physiology*
  • Male
  • Neuroglia
  • Rats
  • Rats, Sprague-Dawley
  • gamma-Aminobutyric Acid / metabolism*

Substances

  • Brain-Derived Neurotrophic Factor
  • gamma-Aminobutyric Acid