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No functional TRPA1 in cardiomyocytes
Author(s) -
Hoebart Clara,
RojasGalvan Natalia S.,
Ciotu Cosmin I.,
Aykac Ibrahim,
Reissig Lukas F.,
Weninger Wolfgang J.,
Kiss Attila,
Podesser Bruno K.,
Fischer Michael J. M.,
Heber Stefan
Publication year - 2021
Publication title -
acta physiologica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.591
H-Index - 116
eISSN - 1748-1716
pISSN - 1748-1708
DOI - 10.1111/apha.13659
Subject(s) - dorsal root ganglion , myocyte , microbiology and biotechnology , trpv1 , induced pluripotent stem cell , cell culture , pathophysiology , transient receptor potential channel , cell type , cell physiology , cell , biology , chemistry , medicine , endocrinology , anatomy , dorsum , receptor , biochemistry , embryonic stem cell , genetics , gene
Aim There is mounting evidence that TRPA1 has a role in cardiac physiology and pathophysiology. We aim to clarify the site of TRPA1 expression in the heart and in particular whether the channel is expressed in cardiomyocytes. Methods Due to the high calcium conductance of TRPA1, and marginal calcium changes being detectable, microfluorimetry in primary mouse cardiomyocytes, and in the cardiomyocyte cell lines H9c2 and HL‐1, was applied. TRPA1 mRNA in mouse and human hearts, primary cardiomyocytes, and the cardiac cell lines were quantified. Dorsal root ganglia served as control for both methods. Results In addition to AITC, the more potent and specific TRPA1 agonists JT010 and PF‐4840154 failed to elicit a TRPA1‐mediated response in native and electrically paced primary cardiomyocytes, and the cardiomyocyte cell lines H9c2 and HL‐1. There were only marginal levels of TRPA1 mRNA in cardiomyocytes and cardiac cell lines, also in conditions of cell differentiation or inflammation, which might occur in pathophysiological conditions. Similarly, TRPV1 agonist capsaicin did not activate primary mouse cardiomyocytes, did not alter electrically paced activity in these, and did not activate H9c2 cells or alter spontaneous activity of HL‐1 cells. Human pluripotent stem cells differentiated to cardiomyocytes had no relevant TRPA1 mRNA levels. Also in human post‐mortem heart samples, TRPA1 mRNA levels were substantially lower compared with the respective dorsal root ganglion. Conclusion The results do not question a role of TRPA1 in the heart but exclude a direct effect in cardiomyocytes.