The Arg389Gly β1-adrenoceptor gene polymorphism influences the acute effects of β-adrenoceptor blockade on contractility in the human heart

Background The β1-adrenoceptor (β1AR) mediates cardiostimulatory effects of catecholamines in the heart. The Arg389Gly polymorphism of the β1AR gene has recently been shown to determine the responsiveness to catecholamines in vitro, and we previously reported that dobutamine induced an augmented contractile response in humans homozygous for the Arg389 allele. The aim of the present study was to evaluate whether the Arg389Gly β1AR gene polymorphism influences the responsiveness to β-blocker treatment on cardiac contractility.