The activation state of β-adrenergic receptors (β-ARs) in vivo is an important determinant of
hemodynamic status, cardiac performance, and metabolic rate. In order to achieve
homeostasis in vivo, the cellular signals generated by β-AR activation are integrated with
signals from a number of other distinct receptors and signaling pathways. We have utilized
genetic knockout models to test directly the role of β1-and/or β2-AR expression on these
homeostatic control mechanisms. Despite total absence of β1-and β2-ARs, the predominant …