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Glial
cell function on postnatal neurogenesis We are
investigating how the interactions between postnatal glial stem cells and neuronal
precursors in the subventricular zone and the cerebellum control neurogenesis
and gliogenesis. The subventricular zone (SVZ) or subependymal zone has been identified
as one of the largest germinal centers that persist in the adult mammalian brain.
The SVZ contains astrocyte-like stem cells and more committed progenitors, which
hold important therapeutic promise. The neonatal cerebellum contains neuronal
precursors that migrate along the radial fibers of Bergmann glial cells. It is
thought that migration and proliferation of SVZ and cerebellar precursors are
influenced by interactions with the precursor environment, including surrounding
stem cells/glial cells and local cues within the SVZ and cerebellum. In the SVZ,
we are investigating whether the neurotransmitter GABA is a signaling factor that
regulates neuronal precursor migration and whether the stem cells control extracellular
GABA levels via specific GABA transporters. In the cerebellum, we are examining
the interactions between Bergmann glial cells and neuronal precursors. We are
addressing these issues in situ, using a slice preparation that maintains the
functionality and the 3-dimentional arrangement of network. We are using various
methods including patch clamping, Ca2+ imaging, time-lapse videomicroscopy and
immunohistochemistry. 
Figure
captions: Postnatal neuronal progenitors of the
mouse SVZ contain GABA (green) Recent publications:
Huang H and Bordey A (2004). Glial glutamate transporters limit spillover activation
of presynaptic NMDA receptors and influence synaptic inhibition of Purkinje neurons.
Journal of Neuroscience. In press.
Wang DD, Krueger DD and Bordey A (2003) GABA
depolarizes postnatal neuronal progenitors of the subventricular zone via GABAA
receptor activation. Journal of Physiology. 550:785-800.
See comments in Perspectives. GABA
exciting again in its own right. Vittorio Gallo and Tarik Haydar (2003).J.
Physiol. Barakat
L and Bordey A (2002). GAT-1
and reversible GABA transport in Bergmann glia in situ. Journal of Neurophysiology
88:1407-19.
Bordey,
A., Lyons, S.A., Hablitz, J.J., and Sontheimer, H. (2001). Electrophysiological
characteristics of reactive astrocytes in experimental cortical dysplasia.
J. Neurophysiol. 2001 Apr;85(4):1719-31.
Barakat, L. and Bordey, A.
(2002). Carrier-mediated
uptake and release of taurine from Bergmann glia in rat cerebellar slices.
J. Physiol. 2002 Jun 15;541(Pt 3):753-67. angelique.bordey@yale.edu http://info.med.yale.edu/neurosur/research/bordey/research.html
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