Western blots were used to quantify caveolin 3, vimentin, and smoothelin expression. Caveolin 3 was found in digested whole tissue and also in the cardiomyocyte fraction but was completely absent from the freshly isolated fibroblast fraction (A).

<p>Vimentin showed strong expression in the fibroblast fraction but was not seen in whole digested tissue or the cardiomyocyte fraction (B). To assess smooth muscle cell contamination, smoothelin immunopositivity was verified in the cardiomyocyte and fibroblast fractions, and compared to pulmonary artery as a positive control (C). Smoothelin was strongly expressed in pulmonary artery but was not present in the cardiomyocyte or fibroblast fraction. N = 3 dogs/group.