화학공학소재연구정보센터
Science, Vol.327, No.5973, 1653-1657, 2010
beta(2)-Adrenergic Receptor Redistribution in Heart Failure Changes cAMP Compartmentation
The beta(1)- and beta(2)-adrenergic receptors (beta ARs) on the surface of cardiomyocytes mediate distinct effects on cardiac function and the development of heart failure by regulating production of the second messenger cyclic adenosine monophosphate (cAMP). The spatial localization in cardiomyocytes of these bARs, which are coupled to heterotrimeric guanine nucleotide-binding proteins (G proteins), and the functional implications of their localization have been unclear. We combined nanoscale live-cell scanning ion conductance and fluorescence resonance energy transfer microscopy techniques and found that, in cardiomyocytes from healthy adult rats and mice, spatially confined beta(2)AR-induced cAMP signals are localized exclusively to the deep transverse tubules, whereas functional beta(1)ARs are distributed across the entire cell surface. In cardiomyocytes derived from a rat model of chronic heart failure, beta(2)ARs were redistributed from the transverse tubules to the cell crest, which led to diffuse receptor-mediated cAMP signaling. Thus, the redistribution of beta(2)ARs in heart failure changes compartmentation of cAMP and might contribute to the failing myocardial phenotype.