暂时的线粒体透性过渡孔口打开介导预条件诱导的保护
Derek Hausenloy1, Abigail Wynne, Michael Duchen
1The Hatter Institute and Centre for Cardiology, University College London, UK.
Circulation
|April 7, 2004
概括
线粒体透性过渡孔 (mPTP) 和反应性氧物种 (ROS) 的暂时开放是心脏预防预条件和解的关键. 抑制mPTP或ROS消除了这些保护作用.
科学领域:
- 心血管研究研究心血管研究
- 线粒体生理学线粒体生理学
- 细胞信号传输 细胞信号传输
背景情况:
- 线粒体透性过渡孔 (mPTP) 的暂时开放影响线粒体水平和反应性氧物种 (ROS) 信号传递.
- 假设这种短暂的mPTP开口能够调解肌肉心预调和线粒体解中观察到的保护作用.
研究的目的:
- 调查短暂的mPTP开放和ROS在调解心肌预调和线粒体解的保护作用中的作用.
主要方法:
- 隔离过的老鼠心经经历了缺血/再输血损伤.
- 在干预后评估了心脏病发作风险与体积的比率.
- 在预条件化方案中使用药理剂来抑制mPTP开放 (环素-A,血素-A) 或ROS (N-mercaptopropionylglycine).
- 氧化物,CCPA和2,4-dinitrophenol用于药理预条件和线粒体解.
主要成果:
- 在预条件化过程中抑制mPTP开放取消了缺血预条件 (IPC),二氧化,CCPA和2,4-丁烯醇的保护作用.
- 抑制ROS消除了IPC,氧化和2,4-丁醇的保护作用,但不是CCPA.
- 在成年大鼠肌细胞中,氧化物诱导了对CSA敏感的,短暂的mPTP开放.
结论:
- IPC,氧化物和线粒体解的保护作用取决于短暂的mPTP开放.
- 对于IPC,氧化物和线粒体解介导的保护机制,ROS信号传递也至关重要.
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