Dataset Information

Accentuated vagal antagonism paradoxically increases ryanodine receptor calcium leak in long-term exercised Calsequestrin2 knockout mice.

ABSTRACT:

Background

Long-term aerobic exercise alters autonomic balance, which may not be favorable in heart rate (HR)-dependent arrhythmic diseases including catecholaminergic polymorphic ventricular tachycardia (CPVT) because of preexisting bradycardia and increased sensitivity to parasympathetic stimulation.

Objective

The purpose of this study was to determine whether long-term exercise-induced autonomic adaptations modify CPVT susceptibility.

Methods

We determined exercise-induced parasympathetic effects on HR, arrhythmia incidence, and intracellular sarcoplasmic reticulum (SR) Ca²⁺ leak in atrial (ACM) and ventricular (VCM) cardiomyocytes, in exercised (EX) calsequestrin knockout (CASQ2^-/-) mice, a model of CPVT.