TRANSLATIONAL PHYSIOLOGY Enhanced sensitivity of aged fibrotic hearts to angiotensin II- and hypokalemia- induced early afterdepolarization-mediated ventricular arrhythmias
نویسندگان
چکیده
Aneesh Bapat,* Thao P. Nguyen,* Jong-Hwan Lee,* Ali A. Sovari, Michael C. Fishbein, James N. Weiss, and Hrayr S. Karagueuzian Translational Arrhythmia Research Section, University of California-Los Angeles (UCLA) Cardiovascular Research Laboratory, and Division of Cardiology, Department of Medicine, UCLA, Los Angeles, California; Department Laboratory Medicine and Pathology, David Geffen School of Medicine, UCLA, Los Angeles, California; and Department of Anesthesiology and Pain Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
منابع مشابه
Enhanced sensitivity of aged fibrotic hearts to angiotensin II- and hypokalemia-induced early afterdepolarization-mediated ventricular arrhythmias.
Unlike young hearts, aged hearts are highly susceptible to early afterdepolarization (EAD)-mediated ventricular fibrillation (VF). This differential may result from age-related structural remodeling (fibrosis) or electrical remodeling of ventricular myocytes or both. We used optical mapping and microelectrode recordings in Langendorff-perfused hearts and patch-clamp recordings in isolated ventr...
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BACKGROUND Hypokalemia is known to promote ventricular arrhythmias, especially in combination with class III antiarrhythmic drugs like dofetilide. Here, we evaluated the underlying molecular mechanisms. METHODS AND RESULTS Arrhythmias were recorded in isolated rabbit and rat hearts or patch-clamped ventricular myocytes exposed to hypokalemia (1.0-3.5 mmol/L) in the absence or presence of dofe...
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Introduction: Inhibition of renin angiotensin system represents an important approach in the management of cardiovascular diseases. The aim of this study was to explore the effects of pretreatment with non-hypotensive dose of angiotensin converting enzyme (ACE) inhibitor, ramiprilat and angiotensin type 1 (AT1) receptor blocker, losartan on myocardial infarct size and arrhythmias in a rat mo...
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