Arrhythmia/Electrophysiology Effect of Nonuniform Muscle Contraction on Sustainability and Frequency of Triggered Arrhythmias in Rat Cardiac Muscle
نویسندگان
چکیده
be induced by stimulus trains for 7.5 seconds only with the BDM or blebbistatin jet (100 nmol/L isoproterenol, 1.0 mmol/L [Ca ]o, 24°C). During sustained arrhythmias, Ca 2 surges preceded synchronous increases in [Ca ]i, whereas the stoppage of the BDM jet made the Ca surges unclear and arrested sustained arrhythmias (n 6). With 200 nmol/L isoproterenol, 2.5 mmol/L [Ca ]o, and the BDM jet, lengthening or shortening of the muscle during sustained arrhythmias accelerated or decelerated their cycle in both the absence (n 10) and presence (n 10) of 100 mol/L
منابع مشابه
Effect of nonuniform muscle contraction on sustainability and frequency of triggered arrhythmias in rat cardiac muscle.
BACKGROUND Arrhythmias are benign or lethal, depending on their sustainability and frequency. To determine why lethal arrhythmias are prone to occur in diseased hearts, usually characterized by nonuniform muscle contraction, we investigated the effect of nonuniformity on sustainability and frequency of triggered arrhythmias. METHODS AND RESULTS Force, membrane potential, and intracellular Ca(...
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