Role of Imidazoline‐preferring Receptors in the Genesis of Epinephrine‐induced Arrhythmias in Halothane‐anesthetized Dogs

  title={Role of Imidazoline‐preferring Receptors in the Genesis of Epinephrine‐induced Arrhythmias in Halothane‐anesthetized Dogs},
  author={Y. Hayashi and T. Kamibayashi and M. Maze and A. Yamatodani and K. Sumikawa and M. Kuro and I. Yoshiya},
BackgroundDrugs with a central α2-adrenergic action can increase the threshold for halothane-eplnephrine-lnduced arrhythmias. Recently, imidazoline-preferrlng receptors were shown to play a significant role in the hypotensive effect of α2-adrenergic agonists containing an imidazole ring in their structure. To address the question of whether the antiar-rhythmic property of the α2-adrenergic agonists was caused by activation of α2-adrenoceptors or imldazoline-preferrlng receptors in the central… Expand
Antiarrhythmic action of rilmenidine on adrenaline‐induced arrhythmia via central imidazoline receptors in halothane‐anaesthetized dogs
It is suggested that the antiarrhythmic action of rilmenidine is due to the activation of central imidazoline receptors and that vagal tone is critical for this action. Expand
Antiarrhythmic Effect of the Selective I1‐Imidazoline Receptor Modulator Moxonidine on Ouabain‐Induced Cardiac Arrhythmia in Guinea Pigs
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Protective effects of I(1)-antihypertensive agent moxonidine against neurogenic cardiac arrhythmias in halothane-anesthetized rabbits.
The results show that moxonidine presents an antiarrhythmic potency comparable to that of propranolol that should be predominantly related to their central action, however, additional studies are required to determine whether these antiarrHythmic effects are of central and/or peripheral origin. Expand
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It is suggested that the antiarrhythmic effects observed with rilmenidine are mainly mediated by blunting the bicuculline-induced increase in the sympathetic nervous output to the heart and the vascular beds. Expand
Further Characterization of the Receptor Mechanism Involved in the Antidysrhythmic Effect of Dexmedetomidine on Halothane/Epinephrine Dysrhythmias in Dogs
The authors previously reported that dexmedetomidine, a selective alpha2 agonist, prevents the genesis of halothane‐epinephrine dysrhythmias through a central mechanism, and performed the current study to examine the precise receptor mechanism involved in the antidysrhythmic property of dexmedETomidine. Expand
The involvement of pertussis toxin‐sensitive G proteins in the post receptor mechanism of central I1‐imidazoline receptors
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Protective effects of centrally acting sympathomodulatory drugs on myocardial ischemia induced by sympathetic overactivity in rabbits.
It is concluded that clonidine and rilmenidine present cardioprotective effects of central origin, which can be reproduced by propranolol, a lipophilic beta-blocking agent. Expand
Facilitation of spontaneous defibrillation by moxonidine during regional ischaemia in an isolated working rabbit heart model.
In conclusion, moxonidine directly facilitates spontaneous defibrillation of ventricular fibrillation during ischaemia, and it is possible that the defibrillatory action of mox onidine is related to its peripheral antiadrenergic activity, although other mechanisms cannot be excluded. Expand
Arrhythmogenic effect of inhalation anesthetics: biochemical heterogeneity between conduction and contractile systems and protein unfolding.
This chapter summarizes the studies on arrhythmogenic effect of inhalation anesthetics and reviews earlier studies, in which pretreatment of dogs with inhibitors of cyclic-nucleotide phosphodiesterase by methylxanthines induced ventricular fibrillation when challenged with subarrh rhythmogenic doses of epinephrine. Expand
Reduced Hemodynamic Responses to Physical and Mental Stress Under Low-Dose Rilmenidine in Healthy Subjects
The concept that rilmenidine, at a dose lower than the ones recommended to treat hypertension, reduced the myocardial oxygen demand to stress and may carry potential clinical impact is supported. Expand