在人类心室单个肌细胞中,功能性β1和β2 adrenoceptors的共存
F del Monte1, A J Kaumann, P A Poole-Wilson
1Department of Cardiac Medicine, National Heart and Lung Institute, London, England, UK.
Circulation
|September 1, 1993
概括
人类心室肌细胞利用β1和β2 adrenoceptors (AR) 来进行收缩. 在低度的上腺素时,β2AR主要介导心脏衰竭肌细胞的收缩反应.
科学领域:
- 心脏病学 心脏病学
- 分子药理学分子药理学
- 细胞生理学 细胞生理学
背景情况:
- 人类心室表达的β1-上腺受体 (AR) 和β2-AR.
- 这些亚型对心室肌细胞收缩的具体贡献尚未完全阐明.
研究的目的:
- 研究β1-AR和β2-AR在调节单个人类心室肌细胞收缩中的功能作用.
- 确定β1-AR和β2-AR对上腺素诱导的肌细胞收缩的相对贡献.
主要方法:
- 从人类缺陷和非缺陷心室中分离单个肌细胞.
- 在有选择性β1-AR和β2-AR抗剂的存在和缺席下对 (-) - 上腺素的度-反应曲线的构建 (CGP 20712A和ICI 118,551分别).
- 评估收缩幅度,速度,收缩峰值时间和50%放松时间的变化.
主要成果:
- (-) - - 上腺素在人腹腔肌细胞中增加了收缩幅度和速度.
- 对 (-) - 上腺素的反应被β1-AR和β2-AR阻断剂对抗,这表明这两种亚型的贡献是异质的.
- 无论是β1-AR还是β2-AR,都有助于缩短到峰值收缩和放松的时间.
- 在低 (-) -上腺素度下,β2-AR似乎发挥了更为主导的作用,特别是在心脏衰竭的肌细胞中.
结论:
- β1-AR和β2-AR共存,并且在人类心室肌细胞上具有功能活性.
- β1-AR和β2-AR对肌细胞收缩的相对贡献在单个细胞之间有所不同.
- 在失败的人类心脏中,β2-AR主要介导对低度上腺素的收缩反应.
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