Cargando…

LL-VNS attenuates SK2 expression and incidence of arrhythmias following acute myocardial infarction in rats

OBJECTIVES: Our previous study has demonstrated that low-level vagus nerve stimulation (LL-VNS) protects the heart against ventricular arrhythmias (VAs) induced by acute myocardial infarction (AMI). However, the potential mechanisms by which it influences ventricular electrophysiology remain unknown...

Descripción completa

Detalles Bibliográficos
Autores principales: Chen, Mingxian, Zhu, Tongjian, Wu, Zhihong, Hu, Lin, Wu, Zhijian, Liu, Qiming, Zhou, Shenghua
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2023
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9874093/
https://www.ncbi.nlm.nih.gov/pubmed/36712237
http://dx.doi.org/10.3389/fcvm.2022.1034888
_version_ 1784877727896043520
author Chen, Mingxian
Zhu, Tongjian
Wu, Zhihong
Hu, Lin
Wu, Zhijian
Liu, Qiming
Zhou, Shenghua
author_facet Chen, Mingxian
Zhu, Tongjian
Wu, Zhihong
Hu, Lin
Wu, Zhijian
Liu, Qiming
Zhou, Shenghua
author_sort Chen, Mingxian
collection PubMed
description OBJECTIVES: Our previous study has demonstrated that low-level vagus nerve stimulation (LL-VNS) protects the heart against ventricular arrhythmias (VAs) induced by acute myocardial infarction (AMI). However, the potential mechanisms by which it influences ventricular electrophysiology remain unknown. MATERIALS AND METHODS: Forty-five rats were divided into three groups: a Control group (sham AMI followed by sham LL-VNS, n = 15), an AMI group (AMI followed by sham LL-VSN for 60 mins, n = 15), and an AMI + LL-VNS group (AMI followed by LL-VSN for 60 mins, n = 15). Heart rate variability (HRV), ventricular effective refractory period (ERP), ventricular fibrillation threshold (VFT), and left stellate ganglion (LSG) activity were measured at baseline and during AMI. Finally, myocardial tissues were collected for tissue analysis. RESULTS: AMI directly induced hyperactivity in the LSG and reduced vagal tone as indexed by HRV. AMI also decreased VFT, and shortened ERP but increased ERP dispersion. AMI resulted in an increase in expression of ventricular small-conductance Ca(2+)-activated K(+) (SK2). However, LL-VNS significantly mitigated or eliminated the effects of AMI. CONCLUSION: LL-VNS altered the electrophysiological properties of the ventricles through inhibition of cardiac sympathetic nervous activity and reduction in SK2 expression.
format Online
Article
Text
id pubmed-9874093
institution National Center for Biotechnology Information
language English
publishDate 2023
publisher Frontiers Media S.A.
record_format MEDLINE/PubMed
spelling pubmed-98740932023-01-26 LL-VNS attenuates SK2 expression and incidence of arrhythmias following acute myocardial infarction in rats Chen, Mingxian Zhu, Tongjian Wu, Zhihong Hu, Lin Wu, Zhijian Liu, Qiming Zhou, Shenghua Front Cardiovasc Med Cardiovascular Medicine OBJECTIVES: Our previous study has demonstrated that low-level vagus nerve stimulation (LL-VNS) protects the heart against ventricular arrhythmias (VAs) induced by acute myocardial infarction (AMI). However, the potential mechanisms by which it influences ventricular electrophysiology remain unknown. MATERIALS AND METHODS: Forty-five rats were divided into three groups: a Control group (sham AMI followed by sham LL-VNS, n = 15), an AMI group (AMI followed by sham LL-VSN for 60 mins, n = 15), and an AMI + LL-VNS group (AMI followed by LL-VSN for 60 mins, n = 15). Heart rate variability (HRV), ventricular effective refractory period (ERP), ventricular fibrillation threshold (VFT), and left stellate ganglion (LSG) activity were measured at baseline and during AMI. Finally, myocardial tissues were collected for tissue analysis. RESULTS: AMI directly induced hyperactivity in the LSG and reduced vagal tone as indexed by HRV. AMI also decreased VFT, and shortened ERP but increased ERP dispersion. AMI resulted in an increase in expression of ventricular small-conductance Ca(2+)-activated K(+) (SK2). However, LL-VNS significantly mitigated or eliminated the effects of AMI. CONCLUSION: LL-VNS altered the electrophysiological properties of the ventricles through inhibition of cardiac sympathetic nervous activity and reduction in SK2 expression. Frontiers Media S.A. 2023-01-11 /pmc/articles/PMC9874093/ /pubmed/36712237 http://dx.doi.org/10.3389/fcvm.2022.1034888 Text en Copyright © 2023 Chen, Zhu, Wu, Hu, Wu, Liu and Zhou. https://creativecommons.org/licenses/by/4.0/This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Cardiovascular Medicine
Chen, Mingxian
Zhu, Tongjian
Wu, Zhihong
Hu, Lin
Wu, Zhijian
Liu, Qiming
Zhou, Shenghua
LL-VNS attenuates SK2 expression and incidence of arrhythmias following acute myocardial infarction in rats
title LL-VNS attenuates SK2 expression and incidence of arrhythmias following acute myocardial infarction in rats
title_full LL-VNS attenuates SK2 expression and incidence of arrhythmias following acute myocardial infarction in rats
title_fullStr LL-VNS attenuates SK2 expression and incidence of arrhythmias following acute myocardial infarction in rats
title_full_unstemmed LL-VNS attenuates SK2 expression and incidence of arrhythmias following acute myocardial infarction in rats
title_short LL-VNS attenuates SK2 expression and incidence of arrhythmias following acute myocardial infarction in rats
title_sort ll-vns attenuates sk2 expression and incidence of arrhythmias following acute myocardial infarction in rats
topic Cardiovascular Medicine
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9874093/
https://www.ncbi.nlm.nih.gov/pubmed/36712237
http://dx.doi.org/10.3389/fcvm.2022.1034888
work_keys_str_mv AT chenmingxian llvnsattenuatessk2expressionandincidenceofarrhythmiasfollowingacutemyocardialinfarctioninrats
AT zhutongjian llvnsattenuatessk2expressionandincidenceofarrhythmiasfollowingacutemyocardialinfarctioninrats
AT wuzhihong llvnsattenuatessk2expressionandincidenceofarrhythmiasfollowingacutemyocardialinfarctioninrats
AT hulin llvnsattenuatessk2expressionandincidenceofarrhythmiasfollowingacutemyocardialinfarctioninrats
AT wuzhijian llvnsattenuatessk2expressionandincidenceofarrhythmiasfollowingacutemyocardialinfarctioninrats
AT liuqiming llvnsattenuatessk2expressionandincidenceofarrhythmiasfollowingacutemyocardialinfarctioninrats
AT zhoushenghua llvnsattenuatessk2expressionandincidenceofarrhythmiasfollowingacutemyocardialinfarctioninrats