短暂缺血的后果:麻醉,预调和它们的临床影响:第二部分
1Heart Institute, Good Samaritan Hospital, Keck School of Medicine, University of Southern California, Los Angeles, USA. rkloner@goodsam.org
Circulation
|December 19, 2001
概括
短暂的缺血可以通过麻醉损害心脏,导致长期的功能障碍. 然而,它还通过缺血预先调节来保护心脏,减少随后事件造成的损伤.
科学领域:
- 心血管生理学心血管生理学
- 缺血性心脏病是一种心脏病.
背景情况:
- 持续长达15分钟的心肌缺血会导致可逆性损伤,但会引起持久的变化,如心肌麻木.
- 麻醉涉及氧基,改变平衡和潜在的收缩性蛋白质变化,导致后缺血性功能障碍.
- 临床情景包括血管塑造,不稳定性心痛和心肺旁路术后,当麻醉的心肌功能受损时.
研究的目的:
- 探索短暂心肌缺血的双重影响:有害的"麻醉"和保护性的"缺血预先调节".
- 研究心肌麻醉和缺血性预先调节背后的机制.
- 讨论这些现象管理的临床影响和未来的治疗策略.
主要方法:
- 在狗身上进行的实验研究涉及冠状动脉封闭.
- 在各种临床环境中观察丧的心肌.
- 审查涉及氧基,平衡,腺,蛋白激酶C和依赖ATP的通道的机制.
主要成果:
- 短暂的缺血 (长达15分钟) 会导致可逆的肌细胞损伤,但会导致心肌震惊,并导致长时间的收缩功能障碍.
- 缺血性预约,即使是短暂的发作 (5分钟),也显著减少了随后长期缺血的死亡.
- 有证据表明,预条件化可能发生在人类身上,这可以通过减少胸痛症状和心脏活检中的特定代谢变化来表明.
结论:
- 短暂缺血有矛盾的效果:心肌麻醉 (负) 和缺血预先调节 (正).
- 了解这些机制对于开发治疗方法至关重要,以尽量减少麻醉并最大限度地提高预先条件.
- 针对预先条件化的途径的未来药理学药剂为缺血提供了新的治疗方法.
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