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Updated: Mar 11, 2026
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Inducing Plasticity of Astrocytic Receptors by Manipulation of Neuronal Firing Rates
Published on: March 20, 2014
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Dopamine elevates and lowers astroglial Ca2+ through distinct pathways depending on local synaptic circuitry
Alistair Jennings1, Olga Tyurikova1,2, Lucie Bard1
1UCL Institute of Neurology, University College London, London, United Kingdom.
Glia
|November 30, 2016
Summary
Dopamine affects astrocyte calcium levels in the hippocampus, either increasing or decreasing them based on receptor type and brain region. These changes are distinct from dopamine's effects on local synapses.
Area of Science:
- Neuroscience
- Astrocyte Biology
- Neurotransmitter Signaling
Background:
- Astrocyte responses to dopamine in vivo are poorly understood.
- Dopamine's role in modulating astrocyte physiology in the hippocampus remains unclear.
Purpose of the Study:
- To investigate the in situ dopamine sensitivity of hippocampal astrocytes.
- To elucidate the physiological roles and mechanisms of dopamine-induced calcium changes in astrocytes.
Main Methods:
- Whole-cell patch-clamp recording in acute hippocampal slices.
- Life-time imaging of the calcium indicator Oregon Green BAPTA-1.
- Monitoring calcium (Ca2+) in gap junction-connected astrocytes.
Main Results:
- Dopamine induced dose-dependent, bidirectional Ca2+ responses in stratum radiatum astrocytes via D1/D2 receptors.
- Dopamine-evoked Ca2+ decreases in these astrocytes involved D2 receptors and Ca2+ channels.
- Stratum lacunosum moleculare astrocytes showed higher-threshold Ca2+ responses, independent of dopamine receptors.
Conclusions:
- Dopamine can differentially modulate astrocyte calcium levels (increase or decrease) based on receptor subtypes and brain region.
- Astrocyte calcium dynamics are region-specific and can be uncoupled from dopamine's synaptic actions.
- Observed astrocyte Ca2+ elevations reflect diverse underlying cellular mechanisms.
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