布辛多洛的部分激素活性取决于人类β1-上腺体受体的激活状态
Christoph Maack1, Michael Böhm, Lydia Vlaskin
1Klinik und Poliklinik für Innere Medizin III, Universität des Saarlandes, Homburg/Saar, Germany.
Circulation
|July 9, 2003
概括
布辛多洛尔作为人类β1-上腺素受体 (β-ARs) 的部分激动剂. 它在失败的心脏中的活性是由受体激活状态掩盖的,但是在美托普罗罗尔预治疗后揭示出来的.
科学领域:
- 药理学 药理学是指药理学的学科.
- 心血管研究研究心血管研究
- 分子生物学分子生物学
背景情况:
- 布辛多洛尔未能降低心力衰竭的死亡率与其他β-阻塞剂形成鲜明对比.
- 这种差异可能源于布辛多洛尔在β-上腺素受体 (β-ARs) 的部分激素活性.
- 之前关于布辛多洛尔内在活性的研究产生了相互矛盾的结果,可能是由于物种或组织特定的β-AR激活状态.
研究的目的:
- 为了研究bucindolol的内在活性.
- 为了确定物种差异或不同的β-AR激活状态是否解释相互矛盾的布辛多洛尔疗效数据.
- 为了澄清布辛多洛尔在人类心肌衰竭中的机制.
主要方法:
- 评估了布辛多洛尔对与人类β1-AR过度表达的孤立小鼠心房的影响.
- 评估了布辛多洛尔对人类失败的心室肌肉条的收缩力的影响.
- 在心肌制剂中用美托普罗醇或异二醇预处理后检查了布辛多洛尔的作用.
- 与福斯科林反应相关的内效应,以评估β-AR激活.
主要成果:
- 布辛多洛尔增加了小鼠心房的跳动频率,过度表达了人类β1-ARs,这种效应被propranolol阻断了.
- 在人类失败的心肌中,布辛多洛尔在基底条件下没有改变收缩力.
- 梅托普罗洛尔的预处理揭示了布辛多洛尔在人类心肌衰竭中显著的积极无otropic效应.
- 异二醇的预处理取消了沙莫特醇在非失败的心房肌动脉中具有的积极无otropic 作用.
- 布辛多洛尔和沙莫特罗尔的无otropic 作用与福斯科林反应相反相关.
结论:
- 布辛多洛尔是人类β1-AR的部分激动剂.
- 在人类失败的心脏中,布辛多洛尔的部分激动因子被升高的β-AR激活状态所掩盖.
- 梅托普罗洛尔的预治疗揭示了布辛多洛尔在人类心肌衰竭中的部分激素活性.
- 布辛多洛尔的部分激素活性取决于人类β1-AR的激活状态.
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