Differential Bioenergetics in Adult Rat Cardiomyocytes Isolated From the Right Versus Left Ventricle

The right and left ventricle of the heart have distinctly different developmental origins and are affected differently by similar pathological stimuli. Though it is well established that the heart relies almost entirely on mitochondrial function to sustain energy production, it remains unclear whether bioenergetics differ in the two ventricles. Herein, we define a novel methodology to optimize the isolation of intact cardiomyocytes from the right versus the left ventricle. We demonstrate that this segmental Langendorff-free methodology yields viable cardiomyocytes with intact mitochondrial function. Further, we compare bioenergetics in right versus left ventricle cardiomyocytes and show that cardiomyocytes from the right ventricle have a greater maximal capacity for respiration and enhanced glycolytic rate. This increase in respiration was concomitant with increased fatty acid oxidation and levels of fatty acid oxidation proteins, but no change in mitochondrial electron transport complex expression. These data validate a potentially powerful tool to evaluate differences in right and left ventricular function and advance the understanding of cardiac bioenergetic differences. These data will be discussed in the context of differential responses by the right versus ventricle in pathology.