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
Astrocyte Calcium Responses to Sensory Input: Influence of Circuit Organization and Experimental Factors.
Book ChapterDOI
Principles of Transcranial Direct Current Stimulation (tDCS): Introduction to the Biophysics of tDCS
Davide Reato,Ricardo Salvador,Marom Bikson,Alexander Opitz,Jacek P. Dmochowski,Pedro C. Miranda +5 more
TL;DR: This chapter summarizes the current knowledge about the biophysics of transcranial direct current stimulation (tDCS) by illustrating the basic physical principles by which weak electric currents applied transcranially induce an electric field inside the brain.
Journal ArticleDOI
Star power: the emerging role of astrocytes as neuronal partners during cortical plasticity.
TL;DR: Neuronal circuits in the adult cortex are plastic and boosting astrocyte activity enhances plasticity and may be beneficial therapeutically, according to this study.
Proceedings ArticleDOI
A Neural-Astrocytic Network Architecture: Astrocytic calcium waves modulate synchronous neuronal activity
TL;DR: In this article, the authors propose a model of an astrocyte that preserves the experimentally observed spatial allocation of its distinct subcellular compartments, and show how their model may encode, and modulate, the extent of synchronous neural activity via calcium waves that propagate intracellularly across the cells.
Journal ArticleDOI
Ca+ activity maps of astrocytes tagged by axoastrocytic AAV transfer
TL;DR: This work shows that adeno-associated virus particles transfer anterogradely from axons to astrocytes, and uses this axoastrocytic AAV transfer to express genetically encoded Ca2+ indicators at high-contrast circuit specifically.
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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