Increased membrane Ca2+ permeability drives astrocytic Ca2+ dynamics during neuronal stimulation at excitatory synapses.
Glia
; 71(12): 2770-2781, 2023 Dec.
Article
em En
| MEDLINE
| ID: mdl-37564028
ABSTRACT
Astrocytes are intricately involved in the activity of neural circuits; however, their basic physiology of interacting with nearby neurons is not well established. Using two-photon imaging of neurons and astrocytes during higher frequency stimulation of hippocampal CA3-CA1 Schaffer collateral (Scc) excitatory synapses, we could show that increasing levels of released glutamate accelerated local astrocytic Ca2+ elevation. However, blockage of glutamate transporters did not abolish this astrocytic Ca2+ response, suggesting that astrocytic Ca2+ elevation is indirectly associated with an uptake of extracellular glutamate. However, during the astrocytic glutamate uptake, the Na+ /Ca2+ exchanger (NCX) reverse mode was activated, and mediated extracellular Ca2+ entry, thereby triggering the internal release of Ca2+ . In addition, extracellular Ca2+ entry via membrane P2X receptors further facilitated astrocytic Ca2+ elevation via ATP binding. These findings suggest a novel mechanism of activity induced Ca2+ permeability increases of astrocytic membranes, which drives astrocytic responses during neuronal stimulation of CA3-CA1 Scc excitatory synapses.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Astrócitos
/
Neurônios
Idioma:
En
Revista:
Glia
Assunto da revista:
NEUROLOGIA
Ano de publicação:
2023
Tipo de documento:
Article
País de afiliação:
Noruega