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Mechanical Stimulation-induced Calcium Wave Propagation in Cell Monolayers: The Example of Bovine Corneal Endothelial Cells
Published on: July 16, 2013
Damage-induced cell-cell communication in different cochlear cell types via two distinct ATP-dependent Ca waves
Purinergic Signalling
|September 1, 2010
Summary
Two distinct calcium (Ca2+) waves propagate through the cochlea upon damage, triggered by extracellular adenosine triphosphate (ATP) acting on P2 receptors, with different propagation characteristics and cell types involved.
Area of Science:
- Cellular Biology
- Neuroscience
- Auditory System Research
Background:
- Intercellular calcium (Ca2+) waves coordinate cell actions over distances.
- Adenosine triphosphate (ATP) release is crucial for Ca2+ wave propagation in many systems.
- ATP signaling is vital for cochlear development, function, and damage detection.
Purpose of the Study:
- To investigate the distinct Ca2+ waves triggered by cochlear damage.
- To elucidate the mechanisms and cell types involved in these Ca2+ wave propagations.
- To understand the role of P2 receptors in mediating these signals.
Main Methods:
- Induction of damage in cochlear explants.
- Pharmacological manipulation using P2 receptor inhibitors and agonists.
- Measurement of Ca2+ wave velocity, source, and propagation pathways.
- Analysis of cell-specific signaling mechanisms.
Main Results:
- Two distinct Ca2+ waves were identified in damaged cochlear explants.
- A slow wave (14 µm/s) in Deiters' cells involves P2Y receptors and IP3-sensitive stores.
- A fast wave (41 µm/s) in hair cells involves P2X4 receptors and external Ca2+ influx.
Conclusions:
- Extracellular ATP acting on distinct P2 receptors elicits different Ca2+ waves in the cochlea.
- Receptor expression dictates the propagation characteristics of intercellular communication signals in complex tissues.
- This study reveals distinct roles for P2Y and P2X4 receptors in cochlear damage response.
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