RT Journal Article SR Electronic T1 DECELERATOR AND ANTIARRHYTHMIC PROPERTIES OF AMOTRIPHENE JF Journal of Pharmacology and Experimental Therapeutics JO J Pharmacol Exp Ther FD American Society for Pharmacology and Experimental Therapeutics SP 128 OP 136 VO 127 IS 2 A1 Farah, A. A1 Birnbaum, L. YR 1959 UL http://jpet.aspetjournals.org/content/127/2/128.abstract AB The effects of amotriphene, quinidine and procaine amide have been compared on the refractory period and conduction velocity of the isolated atrium of the rabbit. Amotriphene increased the refractory period and was about 4 and 8 times as effective as quinidine and procaine amine, respectively. On conduction velocity, which is decreased by amotriphene and quinidine, both drugs were about equally effective. Amotriphene has powerful decelerator properties which are quantitatively the same in the normal and the epinephrine stimulated isolated rabbit auricle and in the normal and epinephrine stimulated sinus rate of the anesthetized dog. Amotriphene has little effect on epinephrine induced changes in cardiac contractility and blood pressure rise. In experimentally induced auricular flutter and fibrillation, amotriphene produced a reduction in auricular and ventricular rate and reversion to a normal rhythm. Qualitative and quantitative differences between amotriphene and quinidine were found and are discussed.