کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
8475166 | 1550444 | 2013 | 11 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Impaired Na+-dependent regulation of acetylcholine-activated inward-rectifier K+ current modulates action potential rate dependence in patients with chronic atrial fibrillation
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
موضوعات مرتبط
علوم زیستی و بیوفناوری
بیوشیمی، ژنتیک و زیست شناسی مولکولی
بیولوژی سلول
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
Shortened action-potential duration (APD) and blunted APD rate adaptation are hallmarks of chronic atrial fibrillation (cAF). Basal and muscarinic (M)-receptor-activated inward-rectifier K+ currents (IK1 and IK,ACh, respectively) contribute to regulation of human atrial APD and are subject to cAF-dependent remodeling. Intracellular Na+ ([Na+]i) enhances IK,ACh in experimental models but the effect of [Na+]i-dependent regulation of inward-rectifier K+ currents on APD in human atrial myocytes is currently unknown. Here, we report a [Na+]i-dependent inhibition of outward IK1 in atrial myocytes from sinus rhythm (SR) or cAF patients. In contrast, IK,ACh activated by carbachol, a non-selective M-receptor agonist, increased with elevation of [Na+]i in SR. This [Na+]i-dependent IK,ACh regulation was absent in cAF. Including [Na+]i dependence of IK1 and IK,ACh in a recent computational model of the human atrial myocyte revealed that [Na+]i accumulation at fast rates inhibits IK1 and blunts physiological APD rate dependence in both groups. [Na+]i-dependent IK,ACh augmentation at fast rates increased APD rate dependence in SR, but not in cAF. These results identify impaired Na+-sensitivity of IK,ACh as one potential mechanism contributing to the blunted APD rate dependence in patients with cAF. This article is part of a Special Issue entitled “Na+ Regulation in Cardiac Myocytes”.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Molecular and Cellular Cardiology - Volume 61, August 2013, Pages 142-152
Journal: Journal of Molecular and Cellular Cardiology - Volume 61, August 2013, Pages 142-152
نویسندگان
Niels Voigt, Jordi Heijman, Anne Trausch, Elisa Mintert-Jancke, Lutz Pott, Ursula Ravens, Dobromir Dobrev,