A novel approach to the Langendorff technique: preparation of isolated cardiomyocytes and myocardial samples from the same rat heart

New Findings•  What is the central question of this study? The isolation of cardiomyocytes and the homogenization of myocardium are commonly performed on separate rodent hearts. We asked whether it might be viable to derive cells as well as whole muscle (homogenized or cryopreserved) from one organ. •  What is the main finding and its importance? We provide examples of six diverse experiments that can be performed using cells and tissue samples generated by a modified Langendorff technique. The volume and power of resultant data are increased, and the method may be especially beneficial in models of cardiovascular disease.Researchers in biomedical sciences must continually re‐evaluate their investment in experiments using laboratory animals. Our group is interested in various signalling pathways that underlie physiological and pathophysiological functioning of the mammalian heart. Two important resources for this type of work are isolated cardiomyocytes and homogenized or preserved sections of whole myocardium. In order to improve our experimental approach ethically, we devised an adaptation of the Langendorff whole‐heart retrograde perfusion technique that allows the isolation of adult rat ventricular cardiomyocytes and processing/storage of myocardium from the same heart. This could result in a 50% reduction in the number of animals required for certain experiments. We believe that a generalized adoption of this method would represent a meaningful reduction of animal use in our field of research and, furthermore, strengthen data sets by permitting correlation between myocyte function and various parameters of myocardial biochemistry/structure in individual hearts. This approach is of particular relevance for studies of cardiac pathology, given the cost and time involved in generating experimental disease models.