Adenosine enhances acetylcholine receptor channel openings and intracellular calcium 'spiking' in mouse skeletal myotubes. (4th March 2015)

• Record Type: Journal Article
• Authors: Bernareggi, A.; Luin, E.; Pavan, B.; Parato, G.; Sciancalepore, M.; Urbani, R.; Lorenzon, P.
• Is Part Of: Acta physiologica. Volume 214:Number 4(2015:Aug.)
• Page Start: 467
• Page End: 480
• Publication Date: 2015-03-04
• Subjects: Physiology -- Periodicals; Physiology -- Research -- Periodicals; 612
• DOI: 10.1111/apha.12473
• Languages: English
• ISSNs: 1748-1708

Abstract

<abstract abstract-type="main" id="apha12473-abs-0001"> <title>Abstract</title> <sec id="apha12473-sec-0001" sec-type="section"> <title>Aims</title> <p>The autocrine activity of the embryonic isoform of the nicotinic acetylcholine receptor is crucial for the correct differentiation and trophism of skeletal muscle cells before innervation. The functional activity of extracellular adenosine and adenosine receptor subtypes expressed in differentiating myotubes is still unknown. In this study, we performed a detailed analysis of the role of adenosine receptor‐mediated effects on the autocrine‐mediated nicotinic acetylcholine receptor channel openings and the associated spontaneous intracellular calcium 'spikes' generated in differentiating mouse myotubes <italic>in vitro</italic>.</p> </sec> <sec id="apha12473-sec-0002" sec-type="section"> <title>Methods</title> <p>Cell‐attached patch‐clamp recordings and intracellular calcium imaging experiments were performed in contracting myotubes derived from mouse satellite cells.</p> </sec> <sec id="apha12473-sec-0003" sec-type="section"> <title>Results</title> <p>The endogenous extracellular adenosine and the adenosine receptor‐mediated activity modulated the properties of the embryonic isoform of the nicotinic acetylcholine receptor in myotubes <italic>in vitro</italic>, by increasing the mean open time and the open probability of the ion channel, and sustaining nicotinic acetylcholine receptor‐driven intracellular [Ca<sup>2+</sup>]<sub>i</sub> 'spikes'. The pharmacological characterization of the adenosine receptor‐mediated effects suggested a prevalent involvement of the A<sub>2B</sub> adenosine receptor subtype.</p> </sec> <sec id="apha12473-sec-0004" sec-type="section"> <title>Conclusion</title> <p>We propose that the interplay between endogenous adenosine and nicotinic acetylcholine receptors represents a potential novel strategy to improve differentiation/regeneration of skeletal muscle.</p> </sec> </abstract>