Amiodarona causa vasodilatação dependente do endotélio em artérias coronárias caninas

Translated title of the contribution: Amiodarone causes endothelium-dependent vasodilation in canine coronary arteries

Alfredo José Rodrigues, Paulo Roberto Barbosa Evora, Ayako Maruo, Hartzell V Schaff

Research output: Contribution to journalArticle

4 Scopus citations


Objective: To assess the vasodilating effects of amiodarone on canine coronary arteries by using solutions of amiodarone dissolved in polysorbate 80 or water. Methods: Rings of coronary arteries, with or without intact endothelium, were immersed in Krebs solution and connected to a transducer for measuring the isometric force promoted by a vascular contraction. The arteries were exposed to increasing concentrations of polysorbate 80, amiodarone dissolved in water, amiodarone dissolved in polysorbate 80, and a commercial presentation of amiodarone (Cordarone). The experiments were conducted in the presence of the following enzymatic blockers: only indomethacin, Nω-nitro-L-arginine associated with indomethacin, and only Nω-nitro-L-arginine. Results: Polysorbate 80 caused a small degree of nonendothelium-dependent relaxation. Cordarone, amiodarone dissolved in water, and amiodarone dissolved in polysorbate 80 caused endothelium-dependent relaxation, which was greater for amiodarone dissolved in polysorbate and for Cordarone. Only the association of indomethacin and Nω-nitro-L-arginine could eliminate the endothelium-dependent relaxation caused by amiodarone dissolved in polysorbate 80. Conclusion: The results obtained indicate that vasodilation promoted by amiodarone in canine coronary arteries is mainly caused by stimulation of the release of nitric oxide and cyclooxygenase-dependent relaxing endothelial factors.

Original languageUndefined
Pages (from-to)251-255
Number of pages5
JournalArquivos Brasileiros de Cardiologia
Issue number3
StatePublished - Mar 2005
Externally publishedYes



  • Amiodarone
  • Coronary circulation Faculdade de Medicina de Ribeirao Preto da USP
  • Cyclooxygenase
  • Endothelium
  • Nitric oxide

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine

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