Calcium entry through a subpopulation of AMPA receptors desensitized neighbouring NMDA receptors in rat dorsal horn neurons.
AUTOR(ES)
Kyrozis, A
RESUMO
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.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1157999Documentos Relacionados
- Ca(2+)-dependent inactivation of NMDA receptors: fast kinetics and high Ca2+ sensitivity in rat dorsal horn neurons.
- Mechanisms of GABA and glycine depolarization-induced calcium transients in rat dorsal horn neurons.
- Lanthanum actions on excitatory amino acid-gated currents and voltage-gated calcium currents in rat dorsal horn neurons.
- Voltage-dependent interaction of open-channel blocking molecules with gating of NMDA receptors in rat cortical neurons.
- Calcium-induced calcium release in rat sensory neurons.