Importantly, the differential and time‐specific changes in cardiac Epac1/2, PKA subunits, CaMKII and the phosphorylation status of PLB and TnI in diabetic myocardium that we delineate herein at the level of the whole heart, suggest potential modifications in the regulation of specific subcellular cAMP and Ca2+ pools, which would require further characterization for a better understanding of how cAMP and Ca2+ compartmentalization is remodelled in DCM. The gene discussed is RAPGEF3; the disease is familial dilated cardiomyopathy.