P2 receptors and neuronal injury
Heike Franke1, Ute Krügel, Peter Illes
1Rudolf-Boehm Institute of Pharmacology and Toxicology, University of Leipzig, Härtelstrasse 16-18, 04107, Leipzig, Germany. Heike.Franke@medizin.uni-leipzig.de
Pflugers Archiv : European Journal of Physiology
|April 29, 2006
Summary
Extracellular adenosine 5'-triphosphate (ATP) acts as a signaling molecule in the brain, influencing neuron and glial cell communication via P2 receptors. Its release and modulation are key to understanding brain injury and potential therapeutic strategies.
Area of Science:
- Neuroscience
- Cell Signaling
- Neuroinflammation
Background:
- Extracellular adenosine 5 '-triphosphate (ATP) is an activity-dependent signaling molecule.
- ATP modulates glia-glia and glia-neuron communications, acting as a neurotransmitter and cotransmitter.
- ATP effects are mediated by P2X and P2Y receptors, influencing synaptic transmission and neuronal damage/regeneration.
Purpose of the Study:
- To review the role of purinergic mechanisms in brain insults.
- To highlight P2 receptor-mediated neurodegenerative and neuroprotective processes.
- To discuss potential therapeutic manipulations of purinergic signaling.
Main Methods:
- Literature review focusing on purinergic signaling in the central nervous system.
- Analysis of ATP release mechanisms (exocytosis, transporters, hemichannels) and cellular damage.
- Examination of P2 receptor functions in neuronal and glial cells under physiological and pathophysiological conditions.
Main Results:
- Extracellular ATP release is a widespread physiological process, also occurring during cellular damage.
- P2 receptor activation in neurons and glia contributes to both detrimental and beneficial effects in brain injury.
- Purinergic mechanisms, particularly massive ATP release, correlate with the etiopathology of brain insults.
Conclusions:
- Purinergic signaling, mediated by P2 receptors, plays a critical role in the response to brain injury.
- Understanding ATP's dual role in neurodegeneration and neuroprotection is crucial for developing therapeutic strategies.
- Modulation of P2 receptor activity offers potential for treating brain insults.
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