Mitochondrial dysfunction on sinoatrial node and pulmonary vein electrophysiological activities

Yung Kuo Lin, Chen Chuan Cheng, Min Chien Tsai, Pei Yu Wu, Yi Ann Chen, Yao Chang Chen, Shih Ann Chen, Yi Jen Chen

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

Atrial fibrillation (AF) is associated with mitochondrial dysfunction. Sinoatrial node (SAN) dysfunction increases arrhythmogenesis of pulmonary veins (PVs), which is the most important trigger of AF; however, it is not clear whether mitochondrial dysfunction differentially regulates electrical activity of SANs and PVs. In the present study, conventional microelectrodes were used to record the action potentials (APs) in isolated rabbit PVs, SANs, left atrium (LA) and right atrium (RA) before and after application of trifluorocarbonylcyanide phenylhydrazone (FCCP; a mitochondrial uncoupling agent) at 10, 100 and 300 nM. FCCP application at 100 and 300 nM decreased spontaneous rates in PVs and in SANs at 10, 100 and 300 nM. FCCP shortened the 20, 50 and 90% AP durations in the LA, and shortened only the 20% AP duration in the RA. FCCP caused a greater rate reduction in SANs than in PVs; however, in the presence of coenzyme-Q10 (10 µM), FCCP reduced the beating rate in PVs and SANs to a similar extent. In SAN-PV preparations with intact electrical connections, FCCP (100 nM) application shifted the SAN-PV electrical conduction into PV-SAN conduction in 5 (62.5%) of 8 preparations. In conclusion, mitochondrial dysfunction modulates PV and SAN electrical activities, which may contribute to atrial arrhythmogenesis.

Original languageEnglish
Pages (from-to)2486-2492
Number of pages7
JournalExperimental and Therapeutic Medicine
Volume13
Issue number5
DOIs
Publication statusPublished - May 1 2017

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Keywords

  • Atrial fibrillation
  • Mitochondrial dysfunction
  • Pulmonary vein
  • Sinoatrial node

ASJC Scopus subject areas

  • Immunology and Microbiology (miscellaneous)
  • Cancer Research

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