[Similarity of the effects of first-generation antiarrhythmia agents and decreased extracellular concentration of sodium ions on action potentials of atrial myocytes].
In rabbit right atria beating in a spontaneous sinus rhythm, myocytes of two types were studied, which differ by the initial form of action potentials. First-class antiarrhythmics and a gradual decrease in extracellular Na+ concentration induced qualitatively similar and unidirectional changes in the form of action potentials of myocytes. In some myocytes of the "conducting system" type, a slow diastolic depolarization was observed after repolarization, and the form of their action potentials became similar to that of the pacemaker cells. An enhancement of the action caused short-time arrhythmias.
Institute of Cardiology, Kaunas Medical Academy, Lithuania.
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I
Grigaliunene
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M
Skuchas
D000200:Action Potentials / Q000187:drug effects*; D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology*; D016275:Atrial Function; D005110:Extracellular Space / Q000378:metabolism*; D006325:Heart Atria / Q000187:drug effects; D066298:In Vitro Techniques; D011817:Rabbits; D012964:Sodium / Q000378:metabolism*
D000889:Anti-Arrhythmia Agents; D012964:Sodium
Skhodstvo vozdeĭstviia antiaritmikov pervogo klassa i ponizhennoĭ vnekletochnoĭ kontsentratsii ionov natriia na potentsialy deĭstviia miotsitov predserdiia.