EFFECT OF DIFFERENT BETA-BLOCKING-AGENTS ON AN INVITRO MODEL OF VENTRICULAR AUTOMATICITY

  • 1 January 1982
    • journal article
    • research article
    • Vol. 4  (5) , 307-311
Abstract
The effect of 7-.beta.-blocking agents with different properties, such as quinidine-like activity (QLA) or intrinsic sympathomimetic activity (ISA), was tested on a model of automaticity induced in the isolated right ventricle of the rat. Propranolol was the most effective drug for the inhibition of the automatic activity. Pronethalol, pindolol and labetalol also decreased the automatic rate; acebutolol was less effective than these 3 drugs but with larger concentrations also decreased the preparation''s frequency. Neither sotalol nor practolol decreased the preparation''s frequency, but practolol increased that frequency at higher concentrations. QLA might play an important role in the antidysrhythmic efficacy of these compounds which might be antagonized by ISA.