Age-associated alternations in cardiac β-adrenergic receptor signaling
Jing MA
Shiwen WANG
Ruiping XIAO
摘要：During aging, cardiac contractile response to β-AR stimulation is decreased in humans and animal models. Recent studies demonstrate that the positive inotropic effects of both β1-AR and β2-AR stimulation are significantly decreased with aging.This is accompanied by decreases in both β-AR subtype densities and a reduction in membrane adenylyl cyclase activity. However,neither G protein-coupled receptor kinases (GRKs) nor inhibitory G proteins (Gi) appears to contribute to the age-associated reduction in the β-AR modulation of contraction. Thus, while both aging and chronic heart failure exhibit a diminution in cardiac β-AR responsiveness, only heart failure exhibits increased GRK-mediated desensitization ofβ-Ars and an upregulation of Gi proteins.
机标关键词：
分类号：R3(基础医学)
论文发表日期：2005-10-01
在线出版日期：2025-08-15（本平台首次上网日期，不代表文献的发表时间）
页数：4( 254-257 )