PO-02-241 CARDIAC SYMPATHETIC REMODELING AND SK CHANNELS UPREGULATION, THE POSSIBLE MECHANISMS OF NOISE EXPOSURE ASSOCIATED ATRIAL ARRHYTHMOGENESIS
نویسندگان
چکیده
Environmental noise exposure may increase sympathetic tone and lead to atrial fibrillation (AF) mortality. The small conductance Ca2+- activated K+ (SK) channels play important roles in the repolarization of atria. regulation SK might be involved modulating cardiac electrophysiology via autonomic nervous system (ANS). Apamin blocks specifically is used for evaluating related exposure. To determine how ANS regulates under We a (NOE) mice model with broad-band 20-20k Hz 28 days induce myopathy. A total 12 NOE 9 control were study. Dual optical mapping was performed Langendorff perfused intact hearts measure baseline post-apamin action potential duration (APD), calcium transient (CaTD) conduction velocity (CV) mice. expression channel proteins (SK1-3), tyrosine hydroxylase (TH) growth-associated protein 43 (GAP43) detected by immunohistochemistry. degree myocardial fibrosis atria Masson's trichrome staining. Optical study showed no APD difference (26.26±3.69 vs 27.76±2.36 ms, p=0.69) but prolonged CaTD (52.67±1.91 49.65±3.4 p=0.03) compared at baseline. ratio ΔAPD (the after before apamin) higher than (0.221±0.231 0.011±0.52, p=0.015), meaning that contributed upregulation channels. Atrial CV (44.9±4 39.2±3.5 cm/s, p=0.019); apamin administration, it significantly lower (30.9±4.8 34.2±3.5 p=0.045). IHC SK1-3, TH, GAP43 staining (18445.3±2527.9 11228.4±2276.9 μm2/ mm2, 16063.6±1974 9760.17±2576.8 μm2/mm2, 9304.3±633.1 5994.7±1131.8 1019.9±189.8 622.6±252.3 733.5±449.1 117.4±53.4 7449.9±4274.7 492.6±353.9 all p≤0.01). Additionally, AF can induced 17% (2/12) never (p=0.14). Noise induces remodeling, currents upregulation. It partially explains mechanism noise-induced arrhythmia.
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ژورنال
عنوان ژورنال: Heart Rhythm
سال: 2023
ISSN: ['1556-3871', '1547-5271']
DOI: https://doi.org/10.1016/j.hrthm.2023.03.753