%0 Journal Article
%T Age-associated alternations in cardiac P -adrenergic receptor signaling<br>Age-associated alternations in cardiac β-adrenergic receptor signaling
%A Jing MA
%A Shiwen WANG
%A Ruiping XIAO
%A <br>Jing MA
%A Shiwen WANG
%A Ruiping XIAO
%J 老年心脏病学杂志(英文版)
%D 2005
%I Science Press
%X During aging, cardiac contractile response to P-AR stimulation is decreased in humans and animal models. Recent studies demonstrate that the positive inotropic effects of both f^-AR and P2-AR stimulation are significantly decreased with aging. This is accompanied by decreases in both P-AR subtype densities and a reduction in membrane adenylyl cyclase activity. However, neither G protein-coupled receptor kinases (GRKs) nor inhibitory G proteins (G.) appears to contribute to the age-associated reduction in the P-AR modulation of contraction. Thus, while both aging and chronic heart failure exhibit a diminution in cardiac P-AR responsiveness, only heart failure exhibits increased GRK-mediated dcsensitization of p-ARs and an upregulation of G proteins.
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=A9DB1C13C87CE289EA38239A9433C9DC&cid=AD36F34DDC3BA7B0&jid=4DC702B3A2386A4814E2FF9CFB799B27&aid=321F3375700592C7FA961D3B9FE35004&yid=2DD7160C83D0ACED&vid=0B39A22176CE99FB&iid=E158A972A605785F&sid=01622E3E475F966C&eid=4290346F7268639E&journal_id=1671-5411&journal_name=Journalofgeriatriccardiology:JGC&referenced_num=0&reference_num=0