Direct effects of apelin on cardiomyocyte contractility and electrophysiology

Klára Farkasfalvi, Mark A. Stagg, Steven R. Coppen, Urszula Siedlecka, Joon Lee, Gopal K. Soppa, Nándor Marczin, István Szokodi, Magdi H. Yacoub, Cesare M.N. Terracciano

Research output: Contribution to journalArticle

108 Citations (Scopus)


Apelin, the ligand for the angiotensin receptor like-1, has been implicated in the pathogenesis of atrial fibrillation and heart failure. However, it is unknown if apelin has direct effects on cardiomyocyte contractility and electrophysiology. APJ-like immunoreactivity was localized to T-tubules and intercalated disc area in isolated adult rat ventricular myocytes. Apelin (1 nM) significantly increased sarcomere shortening in normal as well as failing cardiomyocytes. The transient increase in shortening was not accompanied by increased [Ca2+] transient amplitude. Apelin significantly activated the sarcolemmal Na+/H+ exchanger (NHE) and increased intracellular pH. Moreover, apelin (10 nM) increased conduction velocity in monolayers of cultured neonatal rat cardiac myocytes. Our results demonstrate for the first time that apelin has direct effects on the propagation of action potential and contractility in cardiomyocytes. One of the mechanisms involved in the inotropic effect may be an increased myofilament sensitivity to Ca2+ as apelin enhanced the activity of NHE with consequent intracellular alkalinization.

Original languageEnglish
Pages (from-to)889-895
Number of pages7
JournalBiochemical and biophysical research communications
Issue number4
Publication statusPublished - Jun 15 2007



  • Cell communication
  • Inotropic agents
  • Myocytes
  • Na/H exchanger
  • Peptide hormones

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Molecular Biology
  • Cell Biology

Cite this

Farkasfalvi, K., Stagg, M. A., Coppen, S. R., Siedlecka, U., Lee, J., Soppa, G. K., Marczin, N., Szokodi, I., Yacoub, M. H., & Terracciano, C. M. N. (2007). Direct effects of apelin on cardiomyocyte contractility and electrophysiology. Biochemical and biophysical research communications, 357(4), 889-895.