β-Adrenergic axis and heart disease

β-Adrenergic receptors (β-ARs) belong to a large family of G-protein-coupled receptors (GPCRs) that form the interface between the sympathetic nervous system and the cardiovascular system. The β-AR signal system is one of the most powerful regulators of cardiac function, mediated by the effects of the sympathetic transmitters epinephrine and norepinephrine. In a number of cardiac diseases, however, the biology of β-AR signaling pathways is altered dramatically. Here we discuss the role of β-AR signaling in the normal and abnormal heart and how the use of genetically engineered mouse models has helped in our understanding of the pathophysiology of cardiac disease.