Dopamine elevates and lowers astroglial Ca2+ through distinct pathways depending on local synaptic circuitry
| Autor: | Jennings, Alistair, Tyurikova, Olga, Bard, Lucie, Zheng, Kaiyu, Semyanov, Alexey, Henneberger, Christian, Rusakov, Dmitri A |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
drug effects [Excitatory Postsynaptic Potentials]
Male Patch-Clamp Techniques Dopamine Dopamine Agents drug effects [Astrocytes] pharmacology [Enzyme Inhibitors] drug effects [Synapses] In Vitro Techniques drug effects [Intracellular Fluid] drug effects [Nerve Net] Animals metabolism [Gap Junctions] metabolism [Calcium] ddc:610 metabolism [Dopamine] Enzyme Inhibitors cytology [Astrocytes] Neurotransmitter Agents metabolism [Astrocytes] Dose-Response Relationship Drug metabolism [Intracellular Fluid] Optical Imaging Electric Stimulation drug effects [Gap Junctions] Rats pharmacology [Neurotransmitter Agents] pharmacology [Dopamine Agents] cytology [Hippocampus] physiology [Nerve Net] Calcium pharmacology [Dopamine] |
| Zdroj: | Glia 65(3), 447-459 (2016). doi:10.1002/glia.23103 |
| DOI: | 10.1002/glia.23103 |
| Popis: | Whilst astrocytes in culture invariably respond to dopamine with cytosolic Ca2+ rises, the dopamine sensitivity of astroglia in situ and its physiological roles remain unknown. To minimize effects of experimental manipulations on astroglial physiology, here we monitored Ca2+ in cells connected via gap junctions to astrocytes loaded whole-cell with cytosolic indicators in area CA1 of acute hippocampal slices. Aiming at high sensitivity of [Ca2+ ] measurements, we also employed life-time imaging of the Ca2+ indicator Oregon Green BAPTA-1. We found that dopamine triggered a dose-dependent, bidirectional Ca2+ response in stratum radiatum astroglia, a jagged elevation accompanied and followed by below-baseline decreases. The elevation depended on D1/D2 receptors and engaged intracellular Ca2+ storage and removal whereas the dopamine-induced [Ca2+ ] decrease involved D2 receptors only and was sensitive to Ca2+ channel blockade. In contrast, the stratum lacunosum moleculare astroglia generated higher-threshold dopamine-induced Ca2+ responses which did not depend on dopamine receptors and were uncoupled from the prominent inhibitory action of dopamine on local perforant path synapses. Our findings thus suggest that a single neurotransmitter-dopamine-could either elevate or decrease astrocyte [Ca2+ ] depending on the receptors involved, that such actions are specific to the regional neural circuitry and that they may be causally uncoupled from dopamine actions on local synapses. The results also indicate that [Ca2+ ] elevations commonly detected in astroglia can represent the variety of distinct mechanisms acting on the microscopic scale. GLIA 2017;65:447-459. |
| Databáze: | OpenAIRE |
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