ADRB3 and heart failure: The β3-AR expression inthe myocardium has been shown to be upregulated in heart failure [67, 113, 114].In addition, β3-AR has been reported to signal through endothelialnitric oxide synthase/nitric oxide/cyclic guanosine monophosphate(eNOS/NO/cGMP) pathway for the attenuation of cardiac contractility [90].