[Evaluation of the arrhythmogenic activity of adrenergic and cholinergic agents in calcium chloride arrhythmia]

Under conditions prevailing in an experimental chlorocalcium arrhythmia in rats an anti-arrhythmic action of the sympatholytic-rausedyl, the gamma-adrenolytic-dihydroergo toxin, the beta-adrenolytic--obsidan, the M-cholinolytics--atropine and benactyzine was ascertained. The N-cholinolytics tropacin and hexamethonium had no effect on the parameters and the outcome of the chlorocalcium arrhythmia, whereas the M-cholinomimetic-- carbacholine potentiated the arrhythmogenic action of calcium chloride. The mechanism of the chlorocalcium arrhythmia development the authors attribute to an intensified discharge of epinephrine from the functional depot of the sympathetic nerve endings and to sensitization of the alpha- and beta-adrenoreceptors of the myocardium to the mediator. In the genesis of arrhythmia the participation of M-cholinoreceptors of the myocardium is presumed.