Distinct circadian mechanisms govern cardiac rhythms and susceptibility to arrhythmia.
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ABSTRACT:
SUBMITTER: Hayter EA
PROVIDER: S-EPMC8087694 | biostudies-literature | 2021 Apr
REPOSITORIES: biostudies-literature
Publications
Distinct circadian mechanisms govern cardiac rhythms and susceptibility to arrhythmia.
Hayter Edward A EA Wehrens Sophie M T SMT Van Dongen Hans P A HPA Stangherlin Alessandra A Gaddameedhi Shobhan S Crooks Elena E Barron Nichola J NJ Venetucci Luigi A LA O'Neill John S JS Brown Timothy M TM Skene Debra J DJ Trafford Andrew W AW Bechtold David A DA
Nature communications 20210430 1
Electrical activity in the heart exhibits 24-hour rhythmicity, and potentially fatal arrhythmias are more likely to occur at specific times of day. Here, we demonstrate that circadian clocks within the brain and heart set daily rhythms in sinoatrial (SA) and atrioventricular (AV) node activity, and impose a time-of-day dependent susceptibility to ventricular arrhythmia. Critically, the balance of circadian inputs from the autonomic nervous system and cardiomyocyte clock to the SA and AV nodes di ...[more]
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