Calcium entry through a subpopulation of AMPA receptors desensitized neighbouring NMDA receptors in rat dorsal horn neurons.

TitleCalcium entry through a subpopulation of AMPA receptors desensitized neighbouring NMDA receptors in rat dorsal horn neurons.
Publication TypeJournal Article
Year of Publication1995
AuthorsKyrozis A, Goldstein PA, Heath MJ, MacDermott AB
JournalJ Physiol
Volume485 ( Pt 2)
Pagination373-81
Date Published1995 Jun 1
ISSN0022-3751
Keywordsalpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid, Animals, Calcium, Cells, Cultured, Electrophysiology, Kainic Acid, Neurites, Neuronal Plasticity, Neurons, Patch-Clamp Techniques, Rats, Receptors, AMPA, Receptors, N-Methyl-D-Aspartate, Spinal Cord
Abstract

1. A Ca(2+)-dependent interaction between non-NMDA and NMDA receptors was studied in embryonic rat dorsal horn neurons grown in tissue culture using perforated-patch recording. Specifically, non-NMDA receptors were found to induce reversible inhibition of NMDA receptors in a manner dependent on the presence of extracellular Ca2+. 2. Non-NMDA receptor-induced inhibition of NMDA receptors was mediated by the elevation of intracellular Ca2+ concentration produced by Ca2+ entry through a subpopulation of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate (AMPA) non-NMDA receptors. Furthermore, Ca2+ entry through the AMPA channels alone is sufficient for desensitization of NMDA channels to occur. 3. Imaging of neuritic sites of Ca2+ revealed that Ca(2+)-permeable AMPA channels are often co-localized with NMDA channels on dorsal horn neurons, indicating that the Ca(2+)-mediated interaction between receptors may occur within small dendritic domains. 4. The ability of Ca(2+)-permeable AMPA channels to inhibit adjacent NMDA channels may contribute to the postsynaptic integration of excitatory input.

Alternate JournalJ. Physiol. (Lond.)
PubMed ID7545229
PubMed Central IDPMC1157999
Grant ListGM32099 / GM / NIGMS NIH HHS / United States
NS29797 / NS / NINDS NIH HHS / United States