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Astroglial networks scale synaptic activity and plasticity.

ABSTRACT: Astrocytes dynamically interact with neurons to regulate synaptic transmission. Although the gap junction proteins connexin 30 (Cx30) and connexin 43 (Cx43) mediate the extensive network organization of astrocytes, their role in synaptic physiology is unknown. Here we show, by inactivating Cx30 and Cx43 genes, that astroglial networks tone down hippocampal synaptic transmission in CA1 pyramidal neurons. Gap junctional networking facilitates extracellular glutamate and potassium removal during synaptic activity through modulation of astroglial clearance rate and extracellular space volume. This regulation limits neuronal excitability, release probability, and insertion of postsynaptic AMPA receptors, silencing synapses. By controlling synaptic strength, connexins play an important role in synaptic plasticity. Altogether, these results establish connexins as critical proteins for extracellular homeostasis, important for the formation of functional synapses.

SUBMITTER: Pannasch U

PROVIDER: S-EPMC3100942 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Astroglial networks scale synaptic activity and plasticity.

Pannasch Ulrike U Vargová Lydia L Reingruber Jürgen J Ezan Pascal P Holcman David D Giaume Christian C Syková Eva E Rouach Nathalie N

Proceedings of the National Academy of Sciences of the United States of America 20110502 20

Astrocytes dynamically interact with neurons to regulate synaptic transmission. Although the gap junction proteins connexin 30 (Cx30) and connexin 43 (Cx43) mediate the extensive network organization of astrocytes, their role in synaptic physiology is unknown. Here we show, by inactivating Cx30 and Cx43 genes, that astroglial networks tone down hippocampal synaptic transmission in CA1 pyramidal neurons. Gap junctional networking facilitates extracellular glutamate and potassium removal during sy ...[more]

PMID: 21536893

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Astroglial networks scale synaptic activity and plasticity.

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Astroglial networks scale synaptic activity and plasticity.

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