增加了动脉样硬化的人类冠状动脉的α-上腺激素收缩
1Departments of Cardiology and Pathophysiology (G.H.), Center of Internal Medicine, University of Essen, Germany. dbaum3@t-online.de
Circulation
|April 27, 1999
概括
阿尔法-1 上腺激活不会影响健康动脉的冠状动脉血流,但阿尔法-2 激活会导致收缩. 动脉样硬化加剧了这些影响,可能导致心肌缺血.
科学领域:
- 心脏病学 心脏病学
- 药理学 药理学是指药理学的学科.
- 生理学 生理学 生理学
背景情况:
- 上腺激活与实验性心肌缺血有关.
- 在人类中,α-上腺冠状动脉收缩的作用尚不清楚.
- 这项研究研究了人类冠状动脉中选择性α-上腺素受体激活.
研究的目的:
- 评估选择性α1-和α2-上腺体受体激活对人类冠状动脉血流 (CBF) 的影响.
- 为了确定冠状动脉样硬化是否会影响对α-上腺激动剂的反应.
- 评估阿尔法上腺激活诱导心肌缺血的潜力.
主要方法:
- 在39名患者中,使用结合血管造影和多普勒测试测量了冠状动脉血流 (CBF).
- 选择性α1-激动剂 (甲索胺) 和α2-激动剂 (BHT933) 用于增加剂量.
- 在单个冠状动脉狭窄症患者中评估了心肌乳酸的产量.
主要成果:
- 阿尔法1-上腺激活在正常冠状动脉中没有改变CBF.
- 在冠状动脉狭窄的患者中,α1-和α2-上腺激活剂量依赖地降低了CBF.
- 阿尔法2-上腺激活导致了更大的乳酸净产量,表明心肌缺血症增加.
结论:
- 阿尔法2-上腺激活会导致正常冠状动脉中的微血管收缩.
- 通过α1-和α2-上腺激活诱导的收缩都被动脉样硬化放大.
- 这些影响可以在患有冠状动脉疾病的患者中导致心肌缺血.
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