The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 
 
 

Upregulation of beta-adrenergic receptors in heart failure due to volume overload.

To examine the mechanisms of changes in beta-adrenergic signal transduction in heart failing due to volume overload, we studied the status of beta-adrenoceptors (beta-ARs), G protein-coupled receptor kinase (GRK), and beta-arrestin in heart failure due to aortocaval shunt (AVS). Heart failure in rats was induced by creating AVS for 16 wk, and beta-AR binding, GRK activity, as well as their protein content, and mRNA levels were determined in both left and right ventricles. The density and protein content for beta1-ARs, unlike those for beta2-ARs, were increased in the failing hearts. Furthermore, protein contents for GRK isoforms and beta-arrestin-1 were decreased in membranous fractions and increased in cytosolic fractions from the failing hearts. On the other hand, steady-state mRNA levels for beta1-ARs and GRK2, as well as protein content for Gbetagamma-subunits, did not change in the failing heart. Basal cardiac function was depressed; however, both in vivo and ex vivo positive inotropic responses of the failing hearts to isoproterenol were augmented. Treatment of AVS animals with imidapril (1 mg.kg(-1).day(-1)) or losartan (20 mg.kg(-1).day(-1)) retarded the progression of heart failure; partially prevented changes in beta1-ARs, GRKs, and beta-arrestin-1 in the failing myocardium; and attenuated the increase in positive inotropic effect of isoproterenol. These results indicate that upregulation of beta1-ARs is associated with subcellular redistribution of GRKs and beta-arrestin-1 in the failing heart due to volume overload. Furthermore, attenuation of alterations in beta-adrenergic system by imidapril or losartan may be due to blockade of the renin-angiotensin system in the AVS model of heart failure.[1]

References

  1. Upregulation of beta-adrenergic receptors in heart failure due to volume overload. Wang, X., Sentex, E., Saini, H.K., Chapman, D., Dhalla, N.S. Am. J. Physiol. Heart Circ. Physiol. (2005) [Pubmed]
 
WikiGenes - Universities