[Acute and chronic amiodarone effects on the dynamics of force-interval relationship in rat papillary muscle].
Effects of acute and chronic amiodarone treatment on the force-interval relationship were investigated in rat papillary muscle. It was found that both acute and chronic amiodarone treatment decreased the amplitude of extrasystoles. At the same time, only short-term administgration of amiodarone increased postextrasystols and post-rest potentiations of twitch force in rat myocardium. It is concluded that the acute and chronic amiodarone treatment suppress the excitability of cardiomyocytes, but only the chronic treatment increases the effective refractory period. The results suggest that the acute administration of amiodarone can influence the intracellular calcium homeostasis.
Kondrat'eva
D S
DS
Afanas'ev
S A
SA
Popov
S V
SV
D000638:Amiodarone / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000008:administration & dosage / Q000494:pharmacology*; D004558:Electric Stimulation; D006321:Heart / Q000187:drug effects* / Q000502:physiology; D006352:Heart Ventricles / Q000187:drug effects; D066298:In Vitro Techniques; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D010210:Papillary Muscles / Q000187:drug effects / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D016276:Ventricular Function
D000889:Anti-Arrhythmia Agents; D000638:Amiodarone