Characterization of hERG K + channel inhibition by the new class III antiarrhythmic drug cavutilide.

Autor: Abramochkin DV; Department of Human and Animal Physiology, Biological Faculty, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia. abram340@mail.ru., Pustovit OB; Department of Human and Animal Physiology, Biological Faculty, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia., Mironov NY; Chazov National Medical Research Center for Cardiology, Moscow, Russia., Filatova TS; Department of Human and Animal Physiology, Biological Faculty, Lomonosov Moscow State University, Leninskiye Gory, 1, 12, Moscow, Russia.; Chazov National Medical Research Center for Cardiology, Moscow, Russia.; Department of Physiology, Pirogov Russian National Research Medical University, Ostrovityanova str., 1, Moscow, Russia., Nesterova T; Institute of Immunology and Physiology, Ural Branch of Russian Academy of Sciences, 620049, Ekaterinburg, Russia.; Institute of Natural Sciences and Mathematics, Ural Federal University, 620075, Ekaterinburg, Russia.
Jazyk: angličtina
Zdroj: Naunyn-Schmiedeberg's archives of pharmacology [Naunyn Schmiedebergs Arch Pharmacol] 2024 Jul; Vol. 397 (7), pp. 5093-5104. Date of Electronic Publication: 2024 Jan 15.
DOI: 10.1007/s00210-023-02940-5
Abstrakt: Cavutilide (niferidil, refralon) is a new class III antiarrhythmic drug which effectively terminates persistent atrial fibrillation (AF; 84.6% of patients, mean AF duration 3 months) and demonstrates low risk of torsade de pointes (1.7%). ERG channels of rapid delayed rectifier current(I Kr ) are the primary target of cavutilide, but the particular reasons of higher effectiveness and lower proarrhythmic risk in comparison with other class III I Kr blockers are unclear. The inhibition of hERG channels expressed in CHO-K1 cells by cavutilide was studied using whole-cell patch-clamp. The present study demonstrates high sensitivity of I hERG expressed in CHO-K1 cells to cavutilide (IC50 = 12.8 nM). Similarly to methanesulfonanilide class III agents, but unlike amiodarone and related drugs, cavutilide does not bind to hERG channels in their resting state. However, in contrast to dofetilide, cavutilide binds not only to opened, but also to inactivated channels. Moreover, at positive constantly set membrane potential (+ 60 mV) inhibition of I hERG by 100 nM cavutilide develops faster than at 0 mV and, especially, - 30 mV (τ of inhibition was 78.8, 103, and 153 ms, respectively). Thereby, cavutilide produces I hERG inhibition only when the cell is depolarized. During the same period of time, cavutilide produces greater block of I hERG when the cell is depolarized with 2 Hz frequency, if compared to 0.2 Hz. We suggest that, during the limited time after injection, cavutilide produces stronger inhibition of I Kr in fibrillating atrium than in non-fibrillating ventricle. This leads to beneficial combination of antiarrhythmic effectiveness and low proarrhythmicity of cavutilide.
(© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
Databáze: MEDLINE
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