促成肌细胞预条件在心性停止期间的有益影响的机制
1Department of Anesthesiology, Medical University of South Carolina, Charleston 29425, USA.
Circulation
|November 1, 1996
概括
预条件保护心脏肌肉细胞在模拟心脏停和回暖期间. 这些保护作用由腺通路或ATP敏感通道介导,为心肌保护提供了一种新的方法.
科学领域:
- 心脏病学 心脏病学
- 细胞生物学 细胞生物学
- 身体生理学 身体生理学
背景情况:
- 肌肉心脏预调提供内源性心脏保护在缺血,心脏停和回暖期间.
- 在这些心脏手术过程中,预先调节的好处背后的精确机制仍然不完全理解.
- 这项研究旨在阐明预条件如何在模拟的心脏停和回暖条件下保护肌细胞收缩功能.
研究的目的:
- 调查预条件保护肌细胞收缩功能在模拟心性停止和回暖期间的机制.
- 为了确定非肌细胞细胞群是否有助于预条件的保护作用.
- 为了确定涉及预条件介导心脏保护的特定分子通路.
主要方法:
- 隔离的猪心肌细胞被 subjected to normothermia,模拟心性停止和重新加热,或预先调节之后心性停止和重新加热.
- 视频显微镜评估了肌细胞缩短速度.
- 实验还涉及从预先条件的内皮细胞和平滑肌细胞中取出的物,应用于天真肌细胞.
- 通过增加腺或阿普里卡林的心脏性溶液来探索分子机制.
主要成果:
- 与正常热相比,模拟心性停止和重新加热显著降低了肌细胞缩短速度.
- 预先条件显著改善肌细胞收缩功能在心脏停和回暖后.
- 从预先条件的内皮细胞中分离出来,但不是光滑肌肉细胞,改善肌细胞功能.
- 增加腺或阿普里卡林显著增强肌细胞功能,表明腺通路和对ATP敏感的通道的激活.
结论:
- 前置条件赋予肌细胞收缩功能的保护作用,独立于非肌细胞细胞群.
- 这些保护作用部分通过激活腺路径和对ATP敏感的通道来介导.
- 预先调节与心肌结合使用,为心肌停止和回暖后的心肌保护提供了一种新的策略.
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