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Updated: Aug 15, 2026

Isolation of Human Atrial Myocytes for Simultaneous Measurements of Ca2+ Transients and Membrane Currents
Published on: July 3, 2013
Membrane mechanisms of antiarrhythmic effect of quaternidine
V P Balashov1, D S Blinov, V N Kazachenko
1Department of Medical Biology, N. P. Ogarev Mordovian State University, Saransk, Russia. byp63@yandex.ru
Abstract:
Complex electrophysiological study of the effects of quaternidine carried out on intact hearts from cats, myocardial fragments from rats, and single ionic channels of large edible snail showed that quaternidine demonstrates properties of class 1B antiarrhythmic drug according to Vaughan-Williams nomenclature. This agent did not suppress nomotopic pacemaker automaticity, did not change conduction in ventricles, atria, and atrioventricular junction in hearts with preserved sinus rhythm, did not prolong refractoriness of the atria and atrioventricular junction, but prolonged efficient refractory period of heart ventricles. Quaternidine decelerated rapid depolarization of the action potential, but had no effect on its duration. It did not affect potassium conductance.
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