[Ionic mechanisms of cardiotropic action of a new class III antiarrhythmic drug RG-2].
A perforated patch-clamp analysis of the effect of a novel class III antiarrhythmic agent RG-2, on voltage-dependent currents was made in rat ventricular myocytes. In these cells, RG-2 decreased delayed rectifier outward K(+) current, I(k), in concentration dependent manner with threshold concentration 0.1 microM/l. In contrast, the drug did not have significant effects on the transient outward and inward rectifier K(+) current. RG-2 in concentration dependent manner decreased Ca(2+) current (I(Ca,L)) with threshold concentration 1 microM/l, tenfold higher than threshold concentration for I(k). We can conclude that decreasing of I(k) may explain prolongation of cardiac repolarization induced by RG-2, and contribute to its antiarrhythmic action.
Reznik
A V
AV
Cardiology Research Complex, ul. Tretiya Cherepkovskaya 15a, 121552 Moscow, Russia.
Fedorov
V V
VV
Kokoz
Iu M
IuM
Korystova
A F
AF
Rozenshtraukh
L V
LV
Golitsyn
S P
SP
Ruda
M Ia
MIa
Chazov
E I
EI
D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology*; D002478:Cells, Cultured; D003470:Culture Media; D006321:Heart / Q000187:drug effects*; D006352:Heart Ventricles / Q000166:cytology / Q000187:drug effects; D007473:Ion Channels; D018408:Patch-Clamp Techniques; D026902:Potassium Channel Blockers / Q000494:pharmacology*; D015221:Potassium Channels / Q000187:drug effects; D051381:Rats
D000889:Anti-Arrhythmia Agents; D003470:Culture Media; D007473:Ion Channels; D026902:Potassium Channel Blockers; D015221:Potassium Channels