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[Amiodarone causes endothelium-dependent vasodilation in canine coronary arteries]

Alfredo José Rodrigues1, Paulo Roberto Barbosa Evora, Ayako Maruo

  • 1Faculdade de Medicina de Ribeirão Preto, USP, Ribeirão Preto, SP. alfredo@smnp.usp.br

Arquivos Brasileiros De Cardiologia
|May 4, 2005
PubMed

Insights

Amiodarone causes vasodilation in canine coronary arteries by stimulating nitric oxide and cyclooxygenase-dependent factors. This effect is endothelium-dependent and more pronounced with polysorbate 80 or commercial formulations.

Area of Science:

  • Pharmacology
  • Cardiovascular Physiology

Context:

  • Amiodarone is an antiarrhythmic drug with potential vasodilatory effects.
  • Understanding amiodarone's impact on coronary arteries is crucial for cardiovascular health.
  • Canine coronary arteries serve as a model for studying vascular responses.

Purpose:

  • To investigate the vasodilating effects of amiodarone on canine coronary arteries.
  • To compare the efficacy of amiodarone dissolved in polysorbate 80 versus water.
  • To elucidate the mechanisms underlying amiodarone-induced vasodilation.

Summary:

  • Amiodarone, particularly when dissolved in polysorbate 80 or as a commercial formulation (Cordarone), induced endothelium-dependent vasodilation in canine coronary arteries.
  • Polysorbate 80 alone caused minimal non-endothelium-dependent relaxation.
  • The vasodilation was primarily mediated by nitric oxide and cyclooxygenase-dependent pathways, as evidenced by the blockade of these effects with indomethacin and N-omega-nitro-L-arginine.

Impact:

  • Reveals amiodarone's vasodilatory properties in coronary circulation.
  • Highlights the role of the endothelium and specific signaling pathways in amiodarone's vascular effects.
  • Provides insights into formulation-dependent differences in amiodarone's pharmacological actions.
Abstract

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