Cortical Circuit Activity Evokes Rapid Astrocyte Calcium Signals on a Similar Timescale to Neurons

Jillian L Stobart; Kim David Ferrari; Matthew J P Barrett; Chaim Glück; Michael J Stobart; Marc Zuend; Bruno Weber

doi:10.1016/j.neuron.2018.03.050

Cortical Circuit Activity Evokes Rapid Astrocyte Calcium Signals on a Similar Timescale to Neurons

Neuron. 2018 May 16;98(4):726-735.e4. doi: 10.1016/j.neuron.2018.03.050. Epub 2018 Apr 26.

Authors

Jillian L Stobart¹, Kim David Ferrari², Matthew J P Barrett², Chaim Glück², Michael J Stobart², Marc Zuend², Bruno Weber³

Affiliations

¹ Institute of Pharmacology and Toxicology, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland; Neuroscience Center, University and ETH Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland. Electronic address: [email protected].
² Institute of Pharmacology and Toxicology, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland; Neuroscience Center, University and ETH Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland.
³ Institute of Pharmacology and Toxicology, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland; Neuroscience Center, University and ETH Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland. Electronic address: [email protected].

PMID: 29706581
DOI: 10.1016/j.neuron.2018.03.050

Abstract

Sensory stimulation evokes intracellular calcium signals in astrocytes; however, the timing of these signals is disputed. Here, we used novel combinations of genetically encoded calcium indicators for concurrent two-photon imaging of cortical astrocytes and neurons in awake mice during whisker deflection. We identified calcium responses in both astrocyte processes and endfeet that rapidly followed neuronal events (∼120 ms after). These fast astrocyte responses were largely independent of IP₃R2-mediated signaling and known neuromodulator activity (acetylcholine, serotonin, and norepinephrine), suggesting that they are evoked by local synaptic activity. The existence of such rapid signals implies that astrocytes are fast enough to play a role in synaptic modulation and neurovascular coupling. VIDEO ABSTRACT.

Keywords: GCaMP; RCaMP; astrocyte; calcium signaling; two-photon microscopy; whisker barrel.

Publication types

Research Support, Non-U.S. Gov't
Video-Audio Media

MeSH terms

Adrenergic Agents / pharmacology
Animals
Astrocytes / drug effects
Astrocytes / metabolism*
Atropine / pharmacology
Benzylamines / pharmacology
Calcium Signaling / drug effects
Calcium Signaling / genetics*
Cerebral Cortex / cytology
Cerebral Cortex / drug effects
Cerebral Cortex / metabolism
Inositol 1,4,5-Trisphosphate Receptors / genetics
Intravital Microscopy
Membrane Microdomains / metabolism*
Metergoline / pharmacology
Mice
Mice, Knockout
Muscarinic Antagonists / pharmacology
Neurons / drug effects
Neurons / metabolism*
Optical Imaging
Selective Serotonin Reuptake Inhibitors / pharmacology
Serotonin Antagonists / pharmacology
Somatosensory Cortex / cytology
Somatosensory Cortex / drug effects
Somatosensory Cortex / metabolism*
Spatio-Temporal Analysis
Time Factors
Touch / drug effects
Touch / genetics
Touch / physiology*
Trazodone / pharmacology
Vibrissae

Substances

Adrenergic Agents
Benzylamines
Inositol 1,4,5-Trisphosphate Receptors
Ip3r2 protein, mouse
Muscarinic Antagonists
Serotonin Antagonists
Serotonin Uptake Inhibitors
Metergoline
Atropine
DSP 4
Trazodone