Unchanged G-protein-coupled receptor kinase activity in the aging human heart.
J Am Coll Cardiol
; 42(8): 1487-92, 2003 Oct 15.
Article
em En
| MEDLINE
| ID: mdl-14563597
ABSTRACT
OBJECTIVES:
We sought to find out whether G-protein-coupled receptor kinase (GRK) activity is also increased in the aging human heart.BACKGROUND:
In the aging and failing human heart, cardiac beta-adrenoceptors (beta-AR) are desensitized. In heart failure (HF), an increase in cardiac GRK activity considerably contributes to this beta-AR desensitization.METHODS:
We assessed GRK activity (by in vitro rhodopsin phosphorylation) in the right atria (RA) from 16 children (mean age 9 +/- 2 years) and 17 elderly patients (mean age 67 +/- 2 years) without apparent HF and in the RA from four patients with end-stage HF.Cytosolic and membranous GRK activities in the RA from children were not significantly different from those in elderly patients; in contrast, cytosolic and membranous GRK activities in the RA from patients with end-stage HF were significantly increased.CONCLUSIONS:
In contrast to the failing human heart, in the aging human heart, GRK activity is not increased. Thus, GRK activity appears to not play an important role in beta-AR desensitization in the aging human heart.
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Base de dados:
MEDLINE
Assunto principal:
Envelhecimento
/
Proteínas Quinases Dependentes de AMP Cíclico
/
Apêndice Atrial
/
Miocárdio
Limite:
Adult
/
Aged
/
Child
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Ano de publicação:
2003
Tipo de documento:
Article