Reduced effects of BAY K 8644 on L-type Ca current in failing human cardiac myocytes are related to abnormal adrenergic regulation
نویسندگان
چکیده
Xiongwen Chen, Xiaoying Zhang, David M. Harris, Valentino Piacentino III, Remus M. Berretta, Kenneth B. Margulies, and Steven R. Houser Cardiovascular Research Center and Department of Physiology, Temple University School of Medicine, Philadelphia, Pennsylvania; Duke University School of Medicine, Department of Medicine, Durham, North Carolina; Cardiovascular Research Institute, University of Pennsylvania, Philadelphia, Pennsylvania
منابع مشابه
Reduced effects of BAY K 8644 on L-type Ca2+ current in failing human cardiac myocytes are related to abnormal adrenergic regulation.
Abnormal L-type Ca(2+) channel (LTCC, also named Cav1.2) density and regulation are important contributors to depressed contractility in failing hearts. The LTCC agonist BAY K 8644 (BAY K) has reduced inotropic effects on failing myocardium. We hypothesized that BAY K effects on the LTCC current (I(CaL)) in failing myocytes would be reduced because of increased basal activity. Since support of ...
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The amplification factor of dihydropyridine (DHP)/ryanodine receptors was defined as the amount of Ca2+ released from the sarcoplasmic reticulum (SR) relative to the influx of Ca2+ through L-type Ca2+ channels in rat ventricular myocytes. The amplification factor showed steep voltage dependence at potentials negative to -10 mV but was less dependent on voltage at potentials positive to this val...
متن کاملL-type Ca2+ channel density and regulation are altered in failing human ventricular myocytes and recover after support with mechanical assist devices.
Ca2+ influx through the L-type calcium channel (LTCC) induces Ca2+ release from the sarcoplasmic reticulum (SR) and maintains SR Ca2+ loading. Alterations in LTCC properties, their contribution to the blunted adrenergic responsiveness in failing hearts and their recovery after support with LV assist devices (LVAD) were studied. L-type Ca2+ current (I(Ca,L)) was measured under basal conditions a...
متن کاملL-Type Ca Channel Density and Regulation Are Altered in Failing Human Ventricular Myocytes and Recover After Support With Mechanical Assist Devices
Ca influx through the L-type calcium channel (LTCC) induces Ca release from the sarcoplasmic reticulum (SR) and maintains SR Ca loading. Alterations in LTCC properties, their contribution to the blunted adrenergic responsiveness in failing hearts and their recovery after support with LV assist devices (LVAD) were studied. L-type Ca current (ICa,L) was measured under basal conditions and in the ...
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Human stem cell-derived cardiomyocytes provide a cellular model for the study of electrophysiology in the human heart and are finding a niche in the field of safety pharmacology for predicting proarrhythmia. The cardiac L-type Ca2+ channel is an important target for some of these safety studies. However, the pharmacology of this channel in these cells is altered compared to native cardiac tissu...
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