Results 21 to 30 of about 13,265,348 (295)

Depolarization and Action Potential Duration in Cardiac Purkinje Fibers [PDF]

Circulation Research, 1973
The effect of depolarization on the duration of the action potential was studied in short cardiac Purkinje fibers. Membrane potential was altered by overdriving pacemaker fibers showing spontaneous diastolic depolarization (dog), by injecting constantcurrent pulses through an intracellular microelectrode (sheep), or by voltage clamping (dog).
ARITA, MAKOTO, SURAWICZ, BORYS
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Rate-dependency of action potential duration and refractoriness in isolated myocytes from the rabbit AV node and atrium [PDF]

, 2000
During atrial fibrillation, ventricular rate is determined by atrioventricular nodal (AVN) conduction, which in part is dependent upon the refractoriness of single AVN cells.
Kane, K.A., Rankin, A.C., Workman, A.J.
core   +1 more source

Drug-induced changes in action potential duration are proportional to action potential duration in rat ventricular myocardium

General Physiology and Biophysics, 2010
Several cardioactive agents exhibit direct or reverse rate-dependent effects on action potential duration (APD) depending on the experimental conditions. Recently, a new theory has been proposed, suggesting that the reverse rate-dependent mode of drug-action may be a common property of canine, rabbit, guinea pig and human cardiac tissues, and this ...
László, Bárándi, Gábor, Harmati, Balázs, Horváth, Norbert, Szentandrássy, János, Magyar, András, Varró, Péter P, Nánási, Tamás, Bányász   +7 more
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Action potential in atria.

, 2022
A) Representative action potentials of atrial sinus nodes in WT and PKD2L1del-Tg mice. Basal action potential changes in WT and Tg mice are shown (upper panels). Action potential changes are shown in response to isoproterenol (100 nM, lower panels).
Hirofumi Tomita (525129), Yuichi Toyama (9904498), Shirou Itagaki (6659042), Agnieszka M. Murakami (6659036), Takayoshi Ohba (4597822), Kazuyoshi Hirota (2657692), Takayuki Nemoto (1732558), Manabu Murakami (1786186), Manabu Yonekura (9904501), Yasushi Matsuzaki (9904504), Daisuke Sawamura (9388163), Ichiro Miyoshi (9248771), Yujiro Asada (513646)   +12 more
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Effects of Oxypeucedanin on hKv1.5 and Action Potential Duration

Biological and Pharmaceutical Bulletin, 2005
A furocoumarin derivative, oxypeucedanin, was purified from Angelica dahurica, and its effects on the human Kv1.5 (hKv1.5) channel and on the cardiac action potential duration (APD), were examined using the patch-clamp technique and the conventional microelectrode technique. Oxypeucedanin inhibited the hKv1.5 current in a concentration-dependent manner,
Eun, Jae Soon, Park, Jung Ah, Choi, Bok Hee, Cho, Sun Kyung, Kim, Dae Keun, Kwak, Yong Geun   +5 more
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Instability and Triangulation of the Action Potential Predict Serious Proarrhythmia, but Action Potential Duration Prolongation Is Antiarrhythmic [PDF]

Circulation, 2001
Background—Prolongation of action potential duration (APD) is considered a major antiarrhythmic mechanism (class 2I), but paradoxically, it frequently is also proarrhythmic (torsade de pointes).Methods and Results—The cardiac electrophysiological effects of 702 chemicals (class 2I or HERG channel block) were studied in 1071 rabbit Langendorff-perfused ...
L M, Hondeghem, L, Carlsson, G, Duker
openaire   +2 more sources

Heterogeneities in Ventricular Conduction Following Treatment with Heptanol: A Multi-Electrode Array Study in Langendorff-Perfused Mouse Hearts

Life, 2022
Background: Previous studies have associated slowed ventricular conduction with the arrhythmogenesis mediated by the gap junction and sodium channel inhibitor heptanol in mouse hearts.
Xiuming Dong, Gary Tse, Guoliang Hao, Yimei Du   +3 more
doaj   +1 more source

Stochasticity in Action Potential duration Enhances Dispersion of Repolarisation at Fast Pacing Rates [PDF]

, 2012
Patch clamp recordings of isolated ventricular myocytes frequently display a temporal variability in the action potential duration. Intercellular coupling through gap junctions has been shown to reduce such variability which may return as coupling is ...
Walmsley, John, Rodriguez, Blanca, Pitt-Francis, Joe M., Mirams, Gary R., Burrage, Kevin   +4 more
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Complex Interaction Between Low-Frequency APD Oscillations and Beat-to-Beat APD Variability in Humans Is Governed by the Sympathetic Nervous System

Frontiers in Physiology, 2020
BackgroundRecent clinical, experimental and modeling studies link oscillations of ventricular repolarization in the low frequency (LF) (approx. 0.1 Hz) to arrhythmogenesis.
Stefan Van Duijvenboden, Bradley Porter, Esther Pueyo, Esther Pueyo, David Adolfo Sampedro-Puente, Jesus Fernandez-Bes, Baldeep Sidhu, Justin Gould, Michele Orini, Martin J. Bishop, Ben Hanson, Pier Lambiase, Reza Razavi, Christopher A. Rinaldi, Jaswinder S. Gill, Peter Taggart   +15 more
doaj   +1 more source

Bone Marrow Cell Transplantation into the Heart is Not a Crucial Factor of Ventricular Fibrillation in a Rat Doxorubicin-Induced Cardiomyopathy Model

Journal of Arrhythmia, 2006
To verify the susceptibility of ventricle to arrhythmia after bone marrow mononuclear cell transplantation (BMMNCT), we measured ventricular fibrillation threshold (VFT) and monophasic action potential duration (MAYD90).
Masaki Hamamoto, MD, Shinji Tomita, MD PhD, Masashi Inagaki, MD PhD, Chikao Yutani, MD PhD, Seiji Yamashiro, MD MSc, Kenji Sunagawa, MD PhD, Takeshi Nakatani, MD PhD, Soichiro Kitamura, MD PhD   +7 more
doaj   +1 more source