PROJECT SUMMARY The Physiology and Surgical Core will provide the infrastructure to facilitate increased productivity and synergy between the various projects to aid in defining the mechanisms by which exosomes mediate cell-to- cell communication both within the heart, as well as cross-organ signaling, to regulate pathways involved in cardiac injury and protection. The Core will not only provide a consistent and reproducible service in support of the projects but will further participate in experimental design, prioritization of resources, and the interpretation of data. In addition, Core C will identify additional areas for collaboration across all projects as the program matures and thus be central to the interactive environment and comprehensive analysis of the overall platform as data is generated. The core is a critical aspect to the success of the overall program because it will provide dedicated and highly specialized services to all projects. Perhaps most importantly the core will eliminate much of the noted variability in surgical techniques and protocol variations and thereby enable a direct comparison of results across all projects.