TY - JOUR T1 - THE RÔLE OF ADRENALINE IN THE PRODUCTION OF VENTRICULAR RHYTHMS AND THEIR SUPPRESSION BY ACETYL-β-METHYLCHOLINE CHLORIDE JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 235 LP - 245 VL - 52 IS - 3 AU - H. E. HOFF AU - L. H. NAHUM Y1 - 1934/11/01 UR - http://jpet.aspetjournals.org/content/52/3/235.abstract N2 - 1. Ventricular rhythms arise when the rhythmicity of some ventricular focus exceeds that of the pacemaker. 2. In normal animals intravenous injections of adrenaline produce ventricular rhythms by increasing the rhythmicity of the ventricles while at the same time the rate of the pacemaker is decreased by the depressor reflex. 3. Benzol, chloroform and probably other factors, sensitize the ventricular myocardium to the adrenaline in the body, and in this way so increase the ventricular rhythmicity that ventricular rhythms appear. 4. These ventricular rhythms are readily abolished by acetylcholine (acetyl-β-methylcholine chloride) in appropriate doses. 5. Evidence is presented that acetylcholine not only depresses the rhythmicity of the pacemaker and auricle where vagal endings are known to exist, but also that of the ventricular myocardium. ER -