Journal ArticleDOI
Local Ca2+ detection and modulation of synaptic release by astrocytes
Maria Amalia Di Castro,Julien Chuquet,Nicolas Liaudet,Khaleel Bhaukaurally,Mirko Santello,David Bouvier,Pascale Tiret,Andrea Volterra +7 more
TLDR
Evidence is provided that astrocytes are integrated in local synaptic functioning in adult brain through GTP- and inositol-1,4,5-trisphosphate–dependent signaling and is relevant for basal synaptic function.Abstract:
Astrocytes communicate with synapses by means of intracellular calcium ([Ca(2+)](i)) elevations, but local calcium dynamics in astrocytic processes have never been thoroughly investigated. By taking advantage of high-resolution two-photon microscopy, we identify the characteristics of local astrocyte calcium activity in the adult mouse hippocampus. Astrocytic processes showed intense activity, triggered by physiological transmission at neighboring synapses. They encoded synchronous synaptic events generated by sparse action potentials into robust regional (∼12 μm) [Ca(2+)](i) elevations. Unexpectedly, they also sensed spontaneous synaptic events, producing highly confined (∼4 μm), fast (millisecond-scale) miniature Ca(2+) responses. This Ca(2+) activity in astrocytic processes is generated through GTP- and inositol-1,4,5-trisphosphate-dependent signaling and is relevant for basal synaptic function. Thus, buffering astrocyte [Ca(2+)](i) or blocking a receptor mediating local astrocyte Ca(2+) signals decreased synaptic transmission reliability in minimal stimulation experiments. These data provide direct evidence that astrocytes are integrated in local synaptic functioning in adult brain.read more
Citations
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Journal ArticleDOI
Activity-Dependent Structural Plasticity of Perisynaptic Astrocytic Domains Promotes Excitatory Synapse Stability
Yann Bernardinelli,Jerome Randall,Elia Janett,Irina Nikonenko,Stéphane König,Emma V. Jones,Carmen E. Flores,Keith K. Murai,Christian G. Bochet,Anthony Holtmaat,Dominique Muller +10 more
TL;DR: This study identifies a novel bidirectional interaction between synapses and astrocytes, in which synaptic activity and synaptic potentiation regulate PAP structural plasticity, which in turn determines the fate of the synapse.
Journal ArticleDOI
Astrocytes regulate cortical state switching in vivo
Kira E. Poskanzer,Rafael Yuste +1 more
TL;DR: It is found that astrocytes can indeed trigger the low-frequency state of a cortical circuit by altering extracellular glutamate, and therefore play a causal role in the control of cortical synchronizations.
Book ChapterDOI
Physiology of astroglia
TL;DR: In this chapter, the molecules that achieve ionic gradients and underlie astrocyte signalling are discussed.
Journal ArticleDOI
General anesthesia selectively disrupts astrocyte calcium signaling in the awake mouse cortex
Alexander S. Thrane,Alexander S. Thrane,Vinita Rangroo Thrane,Vinita Rangroo Thrane,Douglas Zeppenfeld,Nanhong Lou,Qiwu Xu,Erlend A. Nagelhus +7 more
TL;DR: This paper found that three commonly used anesthetic combinations (ketamine/xylazine, isoflurane, and urethane) markedly suppressed calcium transients in neocortical astrocytes.
Journal ArticleDOI
Three-dimensional Ca2+ imaging advances understanding of astrocyte biology
Erika Bindocci,Iaroslav Savtchouk,Nicolas Liaudet,Denise Becker,Giovanni Carriero,Andrea Volterra +5 more
TL;DR: 3D imaging in awake mice and in adult brain slices found that Ca2+ activity in an individual astrocyte is heterogeneously scattered throughout the cell, largely compartmented within each region, and preponderantly local.
References
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Journal ArticleDOI
Tripartite synapses: astrocytes process and control synaptic information
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Journal ArticleDOI
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Journal ArticleDOI
Definition of the Readily Releasable Pool of Vesicles at Hippocampal Synapses
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Journal ArticleDOI
Neuronal Synchrony Mediated by Astrocytic Glutamate through Activation of Extrasynaptic NMDA Receptors
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