Reduced aerobic capacity causes leaky ryanodine receptors that trigger arrhythmia in a rat strain artificially selected and bred for low aerobic running capacity.

ABSTRACT:

Aim

Rats selectively bred for inborn low capacity of running (LCR) display a series of poor health indices, whereas rats selected for high capacity of running (HCR) display a healthy profile. We hypothesized that selection of low aerobic capacity over generations leads to a phenotype with increased diastolic Ca(2+) leak that trigger arrhythmia.

Methods

We used rats selected for HCR (N = 10) or LCR (N = 10) to determine the effect of inborn aerobic capacity on Ca(2+) leak and susceptibility of ventricular arrhythmia. We studied isolated Fura-2/AM-loaded cardiomyocytes to detect Ca(2+) handling and function on an inverted epifluorescence microscope. To determine arrhythmogenicity, we did a final experiment with electrical burst pacing in Langendorff-perfused hearts.

Results

SUBMITTER: Hoydal MA 

PROVIDER: S-EPMC3980721 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature