défibrillation 的代谢决定因素. 腺素的作用
1Department of Medicine, New York Hospital-Cornell Medical Center, New York 10021.
Circulation
|February 1, 1995
概括
氨酸通过阻断catecholamine通过A1受体的影响来增加除门 (DFT). 这表明心室动 (VF) 期间的腺释放可能会损害除的成功.
科学领域:
- 心脏病学 心脏病学
- 电力生理学 电力生理学
- 药理学 药理学是指药理学的学科.
背景情况:
- 心室动 (VF) 持续时间对于心脏骤停的结果至关重要,因为它对除门 (DFT) 有影响.
- 缺氧,酸性或性并不会对DFT产生不利影响.
- 在缺氧期间,catecholamine和adenosine水平增加;adenosine对心室肌肉对catecholamine的影响产生对抗作用.
研究的目的:
- 测试延长VF期间腺释放通过抗上腺体机制对DFT产生不利影响的假设.
主要方法:
- 在狗中注入了腺和二皮里达摩尔,以模仿5分钟VF后观察到的腺水平.
- 测量了胸外和心脏外的DFT.
- 在用8-cyclopentyltheophylline (CPT) 阻断A1腺受体后,在无神经状态下重复实验.
主要成果:
- 腺素显著增加了胸前 (49%) 和心脏外 (103%) 的DFT.
- A1腺受体对抗剂CPT完全阻断了腺对DFT的影响.
- 腺素在无神经状态下没有影响DFT,这表明它具有抗上腺体机制.
结论:
- 氨酸通过抗上腺体机制通过A1心肌受体增加DFT.
- 在VF期间腺的升高可能会损害除.
- A1腺素抗剂可能通过降低DFT来促进VF期间的除.
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