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Updated: May 7, 2026

Analyzing the Size, Shape, and Directionality of Networks of Coupled Astrocytes
Published on: October 4, 2018
Subcellular location of astrocytic calcium stores favors extrasynaptic neuron-astrocyte communication
Ilya Patrushev1, Nikolay Gavrilov, Vadim Turlapov
1RIKEN Brain Science Institute, Wako, Saitama, 351-0198, Japan.
Abstract:
Neuron-astrocyte interactions are important for brain computations and synaptic plasticity. Perisynaptic astrocytic processes (PAPs) contain a high density of transporters that are responsible for neurotransmitter clearance. Metabotropic glutamate receptors are thought to trigger Ca(2+) release from Ca(2+) stores in PAPs in response to synaptic activity. Our ultrastructural study revealed that PAPs are actually devoid of Ca(2+) stores and have a high surface-to-volume ratio favorable for uptake. Astrocytic processes containing Ca(2+) stores were located further away from the synapses and could therefore respond to changes in ambient glutamate. Thus, the anatomic data do not support communication involving Ca(2+) stores in tripartite synapses, but rather point to extrasynaptic communication.
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