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Integration of NG2-glia (synantocytes) into the neuroglial network

Published online by Cambridge University Press:  29 September 2009

Rebekah Wigley
Affiliation:
Institute for Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, UK
Arthur M. Butt*
Affiliation:
Institute for Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, UK
*
Correspondence should be addressed to: Arthur M. Butt, Institute for Biomedical and Biomolecular Sciences, School of Pharmacy and Biomedical Sciences, University of Portsmouth, UK email: [email protected]

Abstract

NG2-glia are a distinct class of CNS glial cells that are generally classed as oligodendrocyte progenitor cells. However, in the adult CNS a large fraction of NG2 cells does not appear to divide or generate oligodendrocytes. The functions of these adult NG2-glia, which we have termed synantocytes, are unknown. NG2-glia (synantocytes) form interactive domains with astrocytes and neurons. Within their domains, NG2-glia and astrocytes contact the same neurons, form multiple heterologous contacts with each other, and contact pericytes which regulate cerebral blood flow. NG2-glia receive presynaptic input from neurons and respond to neurotransmitters released at synapses. In addition, NG2-glia are intimately associated with astroglia and respond to astroglial signals, a hitherto neglected aspect of NG2-glial cell physiology. The non-overlapping domain organisation of astrocytes is believed to be important in isolating and integrating activity at the synapses and blood vessels within their domains. The domains of NG2-glia overlap with astrocytes, suggesting they could play a role in integrating non-overlapping astrocyte domains.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2009

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