Aging and sinoatrial node dysfunction: musings on the not-so-funny side.
نویسندگان
چکیده
Coronary Heart Disease Renal Insufficiency Following Contrast Media Administration Trial (REMEDIAL): A Randomized Comparison of 3 Preventive Strategies Carlo Briguori, MD, PhD; Flavio Airoldi, MD; Davide D’Andrea, MD; Erminio Bonizzoni, PhD; Nuccia Morici, MD; Amelia Focaccio, MD; Iassen Michev, MD; Matteo Montorfano, MD; Mauro Carlino, MD; John Cosgrave, MD; Bruno Ricciardelli, MD; Antonio Colombo, MD Clinical Perspective CME ➡ 1211
منابع مشابه
Mapping Cardiac Pacemaker Circuits: Methodological Puzzles of the Sinoatrial Node Optical Mapping [2010;106:255–271] The Role of the Funny Current in Pacemaker Activity Ca Cycling in the Mechanism of Pacemaking Cardiac Pacemaking: Historical Overview and Future Directions
Pacemaker and conduction system myocytes play crucial roles in initiating and regulating the contraction of the cardiac chambers. Genetic defects, acquired diseases, and aging cause dysfunction of the pacemaker and conduction tissues, emphasizing the clinical necessity to understand the molecular and cellular mechanisms of their development and homeostasis. Although all cardiac myocytes of the ...
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It has been shown that the hyperpolarization-activated current “if” that is blocked by 2 mM Cs+ plays a minor role on pacemaker activity of the center and a major role on activity of the periphery of rabbit intact sino-atrial node. On the other hand some investigations showed that if the atrial muscle, surrounding the sino-atrial node, is cut away there is a shift in leading pacemaker site from...
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An inexorable decline in maximum heart rate (mHR) progressively limits human aerobic capacity with advancing age. This decrease in mHR results from an age-dependent reduction in "intrinsic heart rate" (iHR), which is measured during autonomic blockade. The reduced iHR indicates, by definition, that pacemaker function of the sinoatrial node is compromised during aging. However, little is known a...
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Aerobic capacity decreases with age, in part because of an age-dependent decline in maximum heart rate (mHR) and a reduction in the intrinsic pacemaker activity of the sinoatrial node of the heart. Isolated sinoatrial node myocytes (SAMs) from aged mice have slower spontaneous action potential (AP) firing rates and a hyperpolarizing shift in the voltage dependence of activation of the "funny cu...
متن کاملTGF-β1-mediated fibrosis and ion channel remodeling are key mechanisms in producing the sinus node dysfunction associated with SCN5A deficiency and aging.
BACKGROUND Mutations in the cardiac Na(+) channel gene (SCN5A) can adversely affect electric function in the heart, but effects can be age dependent. We explored the interacting effects of Scn5a disruption and aging on the pathogenesis of sinus node dysfunction in a heterozygous Scn5a knockout (Scn5a(+/-)) mouse model. METHODS AND RESULTS We compared functional, histological, and molecular fe...
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عنوان ژورنال:
- Circulation
دوره 115 10 شماره
صفحات -
تاریخ انتشار 2007