Affiliation:
1. Institute for Cardiovascular Diseases, Tokyo Medical and Dental University, Tokyo, Japan
Abstract
Ventricular muscle strips of the rat embryo heart were used for tissue culture preparations without adding trypsin. Fibrillation-like arrhythmia was induced by adding aconitine or strophanthin, and the potentials were recorded with one or two microelectrodes. The tracing by one microelectrode was no different than tracings from fibrillating adult mammalian hearts. The size and shape of the action potential varied beat by beat, and its time of appearance was quite irregular and rapid. But, when tracings obtained simultaneously by two microelectrodes were compared, most of the action potentials were roughly synchronous and thus unlike adult cardiac fibrillation. This ruled out the possibility of multiple reentry or multifocal origin in this preparation.
Because of the small size of the cultured tissue, reentry of the excitation wave probably could not occur, and the conclusion that fibrillation originated from a single focus is thus supported. Three varieties of the onset of fibrillation, i.e., gradual increase of tachycardia with progressively steeper slow diastolic depolarization, a prominent positive afterpotential followed by a negative afterpotential, and abortive action potentials superimposed on the repolarization of the preceding action potentials or on the negative afterpotential, supported the unifocal onset.
Publisher
Ovid Technologies (Wolters Kluwer Health)
Subject
Cardiology and Cardiovascular Medicine,Physiology
Cited by
40 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献