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Updated: Jul 5, 2026
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Inducing Plasticity of Astrocytic Receptors by Manipulation of Neuronal Firing Rates
Published on: March 20, 2014
Synaptic modulation by astrocytes via Ca2+-dependent glutamate release.
1Department of Cell Biology and Morphology, University of Lausanne, Rue du Bugnon 9, 1005 Lausanne, Switzerland.
Neuroscience
|May 6, 2008
Summary
Astrocytes are now known to actively participate in brain information processing by sensing neuronal activity and releasing neurotransmitters like glutamate. This neuron-astrocyte signaling is vital for synapse function and brain communication.
Area of Science:
- Neuroscience
- Cellular Biology
- Neuroimmunology
Background:
- Classical view of astrocytes as passive cells has been overturned.
- Emerging evidence highlights crucial roles of neuron-astrocyte signaling in brain information processing.
- Seminal observations in the 1990s revealed astrocyte responses to neurotransmitters and their release of chemical transmitters.
Purpose of the Study:
- To critically review the characteristics of astrocytic calcium (Ca2+) responses to synaptic activity.
- To discuss the basis of Ca2+-dependent glutamate exocytosis from astrocytes.
- To examine the modes of action of astrocytic glutamate on synaptic function.
Main Methods:
- Literature review and critical discussion of existing research.
- Analysis of studies on astrocyte calcium signaling.
- Investigation of mechanisms of astrocyte-derived glutamate release and action.
Main Results:
- Astrocytes respond to neurotransmitters with intracellular calcium ([Ca2+]i) elevation.
- Astrocytes release neuroactive agents, including glutamate, triggered by [Ca2+]i increases.
- Astrocytic signaling influences synapse formation, function, and plasticity.
Conclusions:
- Astrocytes actively participate in brain information processing.
- Neuron-astrocyte communication expands the concept of brain circuitry.
- Understanding astrocytic roles revolutionizes the view of brain communication.
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