Heteromeric HCN1–HCN4 Channels: A Comparison with Native Pacemaker Channels from the Rabbit Sinoatrial Node
نویسندگان
چکیده
منابع مشابه
HCN4 pacemaker channels attenuate the parasympathetic response and stabilize the spontaneous firing of the sinoatrial node
KEY POINTS The contribution of HCN4 pacemaker channels in the autonomic regulation of the sino-atrial node (SAN) has been a matter of debate. The transgenic overexpression of HCN4 did not induce tachycardia, but reduced heart rate variability, while the conditional knockdown of HCN4 gave rise to sinus arrhythmia. The response of the SAN to β-adrenergic stimulation was not affected by overexpres...
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This article focuses on the regional heterogeneity of the mammalian sinoatrial (SA) node in terms of cell morphology, pacemaker activity, action potential configuration and conduction, densities of ionic currents (i(Na), i(Ca,L), i(to), i(K,r), i(K,s) and i(f)), expression of gap junction proteins (Cx40, Cx43 and Cx45), autonomic regulation, and ageing. Experimental studies on the single SA nod...
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The SCN5A gene encodes specific voltage-dependent Na+ channels abundant in cardiac muscle that open and close at specific stages of cardiac activity in response to voltage change, thereby controlling the magnitude and timecourse of voltage-dependent Na+ currents (iNa) in cardiac muscle cells. Although iNa has been recorded from sinoatrial (SA) node pacemaker cells, its precise role in SA node p...
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ژورنال
عنوان ژورنال: The Journal of Physiology
سال: 2003
ISSN: 0022-3751,1469-7793
DOI: 10.1113/jphysiol.2002.027698