Testing NMDA receptor block as a therapeutic strategy for reducing ischaemic damage to CNS white matter
Autor: | Yamina Bakiri, Nicola B. Hamilton, Ragnhildur Thóra Káradóttir, David Attwell |
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Rok vydání: | 2007 |
Předmět: |
Central Nervous System
N-Methylaspartate Patch-Clamp Techniques Action Potentials Kainate receptor AMPA receptor In Vitro Techniques Biology Pharmacology Receptors N-Methyl-D-Aspartate Article Brain Ischemia Cellular and Molecular Neuroscience Memantine Excitatory Amino Acid Agonists medicine Animals Drug Interactions Receptor Long-term depression Dose-Response Relationship Drug Glutamate receptor Myelin Basic Protein Rats Oligodendroglia Animals Newborn nervous system Neurology Silent synapse NMDA receptor Dizocilpine Maleate Excitatory Amino Acid Antagonists Neuroscience Protein Binding medicine.drug |
Zdroj: | Glia. 56:233-240 |
ISSN: | 1098-1136 0894-1491 |
DOI: | 10.1002/glia.20608 |
Popis: | Damage to oligodendrocytes caused by glutamate release contributes to mental or physical handicap in periventricular leukomalacia, spinal cord injury, multiple sclerosis, and stroke, and has been attributed to activation of AMPA/kainate receptors. However, glutamate also activates unusual NMDA receptors in oligodendrocytes, which can generate an ion influx even at the resting potential in a physiological [Mg2+]. Here, we show that the clinically licensed NMDA receptor antagonist memantine blocks oligodendrocyte NMDA receptors at concentrations achieved therapeutically. Simulated ischaemia released glutamate which activated NMDA receptors, as well as AMPA/kainate receptors, on mature and precursor oligodendrocytes. Although blocking AMPA/kainate receptors alone during ischaemia had no effect, combining memantine with an AMPA/kainate receptor blocker, or applying the NMDA blocker MK-801 alone, improved recovery of the action potential in myelinated axons after the ischaemia. These data suggest NMDA receptor blockers as a potentially useful treatment for some white matter diseases and define conditions under which these blockers may be useful therapeutically. Our results highlight the importance of developing new antagonists selective for oligodendrocyte NMDA receptors based on their difference in subunit structure from most neuronal NMDA receptors. |
Databáze: | OpenAIRE |
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