Incidence of arrhythmias and heart rate variability in wild-type rats exposed to social stress

Sgoifo et al measured arrhythmia occurrence, R-R interval variability, and plasma catecholamine elevations in male wild-type rats exposed to either a social stressor or a nonsocial challenge. Data indicate that a social stressor is characterized by both a high sympathetic activation and a low parasympathetic antagonism, which results in a higher risk for ventricular arrhythmias.