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Updated: Jul 24, 2026
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Two-photon Calcium Imaging in Neuronal Dendrites in Brain Slices
Published on: March 15, 2018
Ca2+ signalling in brain synaptosomes activated by dinucleotides.
M T Miras-Portugal1, J Pintor, J Gualix
1Departamento de Bioquímica, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040 Madrid, Spain. mtmiras@vet.-ucm.es
The Journal of Membrane Biology
|September 23, 2003
Summary
Diadenosine polyphosphates, like Ap5A, are released from nerve terminals and activate receptors, triggering neurotransmitter release. This study shows Ap5A promotes glutamate, GABA, and acetylcholine release in rat brain synaptosomes.
Area of Science:
- Neuroscience
- Molecular Biology
- Biochemistry
Background:
- Diadenosine polyphosphates (Ap4A, Ap5A, Ap6A) are dinucleotides stored in synaptic vesicles.
- These molecules are released upon nerve terminal stimulation and act on extracellular dinucleotide receptors.
- Dinucleotide receptors are ligand-operated ion channels that facilitate cation influx.
Purpose of the Study:
- To investigate the role of diadenosine polyphosphates in neurotransmitter release.
- To characterize the function of dinucleotide receptors in synaptic terminals.
- To determine the effect of Ap5A on the release of specific neurotransmitters.
Main Methods:
- Utilized isolated synaptic terminals (synaptosomes) from rat midbrain.
- Stimulated nerve terminals to induce depolarization and release of diadenosine polyphosphates.
- Measured neurotransmitter release (glutamate, GABA, acetylcholine) following receptor activation.
Main Results:
- Diadenosine polyphosphates stimulate presynaptic dinucleotide receptors.
- Receptor activation, along with calcium channel activation, triggers neurotransmitter release.
- Ap5A was shown to promote the release of glutamate, GABA, and acetylcholine in rat midbrain synaptosomes.
Conclusions:
- Diadenosine polyphosphates play a significant role in modulating neurotransmission.
- Ap5A is implicated as a signaling molecule that enhances the release of key excitatory and inhibitory neurotransmitters.
- These findings contribute to understanding synaptic communication and potential therapeutic targets.
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