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Updated: Aug 12, 2026

Impact of Intracardiac Neurons on Cardiac Electrophysiology and Arrhythmogenesis in an Ex Vivo Langendorff System
Published on: May 22, 2018
Rp-cAMPS has no effect on adenosine A1 receptors in guinea-pig cardiomyocytes
1Imperial College of Science Technology and Medicine, National Heart and Lung Institute, London, UK. d.adamson@ic.ac.uk
Abstract:
Rp-cAMPS, a protein kinase A inhibitor, is used in the investigation of the cAMP-dependent systems. A report by Musgrave et al. has suggested that Rp-cAMPS may also act on adenosine receptors. To determine whether this occurs in guinea-pig ventricular myocytes, Rp-cAMPS was applied in the presence and absence of DCPCX, an adenosine A receptor antagonist. The isoprenaline-induced response was significantly decreased by Rp-cAMPS and the effect was not altered by the presence of DCPCX. Therefore Rp-cAMPS has no effect on cell contraction via adenosine A1 receptors and can reliably be used to investigate cyclic AMP-dependent systems in isolated cardiac myocytes.
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