Rilmenidine prevents epinephrine-induced arrhythmias in halothane-anesthetized dogs

J Cardiovasc Pharmacol. 1995;26 Suppl 2:S40-3.

Abstract

Stimulation of central alpha 2-adrenoceptors has been known to prevent epinephrine-induced arrhythmias in halothane-anesthetized dogs. Because recent studies suggested that several physiological processes that were traditionally attributed to activation of alpha 2-adrenoceptors, such as hypotensive action, are mediated through imidazoline receptors (IRs), it may be likely that IRs are involved in the antiarrhythmic action. We investigated the hypotensive effect of rilmenidine, a selective IR agonist (1, 3, and 10 micrograms/kg i.v.), and the antiarrhythmic effects of the drug on epinephrine-induced arrhythmias during halothane anesthesia in dogs. Although the hypotensive effect of rilmenidine was not remarkable in the dose range we tested, rilmenidine increased the arrhythmogenic threshold for epinephrine in a dose-dependent manner during halothane anesthesia, achieving statistical significance at 10 micrograms/kg, the highest dose we examined. These results suggest that rilmenidine prevents epinephrine-induced arrhythmias during halothane anesthesia and that this effect is more potent than its hypotensive action.

Publication types

  • Comparative Study

MeSH terms

  • Adrenergic alpha-Agonists / therapeutic use*
  • Anesthesia, Inhalation
  • Anesthetics, Inhalation
  • Animals
  • Antihypertensive Agents / therapeutic use*
  • Arrhythmias, Cardiac / chemically induced*
  • Arrhythmias, Cardiac / prevention & control*
  • Dogs
  • Dose-Response Relationship, Drug
  • Epinephrine / antagonists & inhibitors*
  • Female
  • Halothane
  • Imidazoline Receptors
  • Male
  • Oxazoles / therapeutic use*
  • Receptors, Drug / agonists
  • Receptors, Drug / drug effects
  • Rilmenidine

Substances

  • Adrenergic alpha-Agonists
  • Anesthetics, Inhalation
  • Antihypertensive Agents
  • Imidazoline Receptors
  • Oxazoles
  • Receptors, Drug
  • Rilmenidine
  • Halothane
  • Epinephrine