ADRB1 and cardiomyopathy: Isoproterenol (an agonist of β1AR and β2AR), besides being used for bradycardia treatment, has been extensively used to mimic catecholamines in modeling chronic stress-induced cardiomyopathy [hereafter referred to as Isoproterenol-induced cardiomyopathy (ICM)] so as to be able to elucidate its underlying pathomechanisms (8, 9).