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Updated: May 29, 2026
16:38
Dual Electrophysiological Recordings of Synaptically-evoked Astroglial and Neuronal Responses in Acute Hippocampal Slices
Published on: November 26, 2012
Local Ca2+ detection and modulation of synaptic release by astrocytes
Maria Amalia Di Castro1, Julien Chuquet, Nicolas Liaudet
1Department of Cell Biology and Morphology, University of Lausanne, Lausanne, Switzerland.
Nature Neuroscience
|September 13, 2011
Summary
Astrocytes exhibit dynamic calcium activity in their processes, responding to both spontaneous and synchronous synaptic events. This activity is crucial for maintaining normal synaptic function in the adult brain.
Area of Science:
- Neuroscience
- Cellular Biology
- Synaptic Plasticity
Background:
- Astrocytes communicate with neurons via intracellular calcium ([Ca(2+)](i)) signaling.
- Local calcium dynamics within astrocytic processes remain largely uncharacterized.
Purpose of the Study:
- To investigate the characteristics of local astrocyte calcium activity in the adult mouse hippocampus.
- To determine the role of astrocyte calcium signaling in synaptic function.
Main Methods:
- High-resolution two-photon microscopy was employed to visualize astrocyte calcium dynamics.
- Synaptic transmission reliability was assessed under conditions of altered astrocyte calcium signaling.
Main Results:
- Astrocytic processes displayed intense local calcium activity in response to synaptic transmission.
- Astrocytes encoded synchronous synaptic events into regional calcium elevations (∼12 μm).
- Astrocytes detected spontaneous synaptic events, generating confined, fast calcium responses (∼4 μm).
- Astrocyte calcium signaling, dependent on GTP and inositol-1,4,5-trisphosphate, influences synaptic transmission reliability.
Conclusions:
- Astrocytes are dynamically involved in local synaptic functioning in the adult brain.
- Local calcium signaling in astrocytes is essential for maintaining synaptic transmission reliability.
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