Spiking and nonspiking classes of oligodendrocyte precursor glia in CNS white matter.
A defining feature of glial cells has been their inability to generate action potentials. We show here that there are two distinct types of morphologically identical oligodendrocyte precursor glial cells (OPCs) in situ in rat CNS white matter. One type expresses voltage-gated sodium and potassium channels, generates action potentials when depolarized and senses its environment by receiving excitatory and inhibitory synaptic input from axons. The other type lacks action potentials and synaptic input. We found that when OPCs suffered glutamate-mediated damage, as occurs in cerebral palsy, stroke and spinal cord injury, the action potential-generating OPCs were preferentially damaged, as they expressed more glutamate receptors, and received increased spontaneous glutamatergic synaptic input in ischemia. These data challenge the idea that only neurons generate action potentials in the CNS and imply that the development of therapies for demyelinating disorders will require defining which OPC type can carry out remyelination.
Káradóttir
Ragnhildur
R
Department of Physiology, University College London, Gower Street, London WC1E 6BT, UK. rk385@cam.ac.uk
Hamilton
Nicola B
NB
Bakiri
Yamina
Y
Attwell
David
D
D000200:Action Potentials / Q000502:physiology*; D000818:Animals; D000941:Antigens / Q000378:metabolism; D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism; D002450:Cell Communication / Q000502:physiology*; D002490:Central Nervous System / Q000166:cytology / Q000378:metabolism; D005971:Glutamates / Q000494:pharmacology; D066298:In Vitro Techniques; D009413:Nerve Fibers, Myelinated / Q000378:metabolism*; D009419:Nerve Tissue Proteins / Q000378:metabolism; D000076104:Oligodendrocyte Transcription Factor 2; D009836:Oligodendroglia / Q000145:classification* / Q000378:metabolism; D018408:Patch-Clamp Techniques; D024642:Potassium Channels, Voltage-Gated / Q000378:metabolism; D011509:Proteoglycans / Q000378:metabolism; D051381:Rats; D017470:Receptors, Glutamate / Q000187:drug effects / Q000378:metabolism; D015222:Sodium Channels / Q000378:metabolism; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism; D009435:Synaptic Transmission / Q000502:physiology*; D000099216:Chondroitin Sulfate Proteoglycan 4
D000941:Antigens; D051792:Basic Helix-Loop-Helix Proteins; D005971:Glutamates; D009419:Nerve Tissue Proteins; D000076104:Oligodendrocyte Transcription Factor 2; D024642:Potassium Channels, Voltage-Gated; D011509:Proteoglycans; D017470:Receptors, Glutamate; D015222:Sodium Channels; D000099216:Chondroitin Sulfate Proteoglycan 4; C512773:Olig2 protein, mouse