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Updated: Jul 17, 2026
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Single Synapse Indicators of Glutamate Release and Uptake in Acute Brain Slices from Normal and Huntington Mice
Published on: March 11, 2020
Cholinergic interneurons control the excitatory input to the striatum
Pavel Pakhotin1, Enrico Bracci
1Faculty of Life Sciences, University of Manchester, Manchester M60 1QD, United Kingdom.
Summary
A single action potential in a cholinergic interneuron rapidly inhibits glutamate release in the striatum. This presynaptic inhibition, mediated by muscarinic receptors, controls glutamatergic input to striatal neurons.
Area of Science:
- Neuroscience
- Cellular Neuroscience
- Synaptic Plasticity
Background:
- The precise control of presynaptic inhibition by neuronal action potentials is not fully understood.
- Cholinergic interneurons play a crucial role in modulating striatal activity.
Purpose of the Study:
- To investigate how action potentials in cholinergic interneurons influence presynaptic inhibition.
- To determine the time course and extent of this inhibition on glutamatergic inputs.
Main Methods:
- Paired recordings from cholinergic interneurons and projection neurons in the striatum.
- Evoked glutamatergic excitatory postsynaptic potentials (EPSCs) were measured.
- Effects of single cholinergic interneuron spikes and muscarinic receptor antagonists were analyzed.
Main Results:
- A single spike in a cholinergic interneuron significantly depressed evoked glutamatergic EPSCs in projection neurons and other interneurons.
- Inhibition peaked within 20-30 ms and lasted 40-80 ms, with maximal depression up to 27%.
- Muscarinic receptor antagonists blocked these effects and increased baseline EPSCs, indicating tonic cholinergic inhibition.
Conclusions:
- Cholinergic interneurons exert rapid and potent inhibitory control over glutamatergic transmission in the striatum.
- This action is mediated via presynaptic muscarinic receptors.
- A single spike can effectively modulate synaptic input to striatal neurons.
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