在长时间的区域性缺血期间,高能酸盐和乳酸盐释放的反应 in vivo
S Schaefer1, G G Schwartz, J A Wisneski
1Department of Medicine, VA Medical Center, San Francisco, Calif.
Circulation
|January 1, 1992
概括
冬眠心肌减少了维持细胞活力的能量需求. 在长期缺血期间,高能酸盐随着血液流动而减少,而乳酸盐和酸性酶则部分改善,表明缺血减少.
科学领域:
- 心脏病学 心脏病学
- 生物化学 生物化学
- 身体生理学 身体生理学
背景情况:
- 持续的心肌缺血,或心肌缺血,或持续的心肌缺血.
- 在冬眠状态下进行冬眠.
- 心肌,可以通过降低能量需求来保持细胞活力.
- 之前的研究表明,在缺血期间,乳酸代谢和细胞内酸盐的反应各不相同,但不是在相同的流量条件下.
研究的目的:
- 为了研究长期缺血期间高能酸盐和乳酸盐的代谢反应.
- 为了将这些代谢变化与心肌血流和功能相关联.
主要方法:
- 使用31P核磁共振光谱在12个开放胸部的猪.
- 在区域性缺血的2小时内测量下内心血流,段缩短,高能酸盐 (ATP,PCr) 和乳酸释放.
- 在整个缺血期监测pH值变化.
主要成果:
- 在缺血期间,心下内脏血流和段缩短显著减少.
- 与血液流动平行下降的ATP,脂蛋白 (PCr) 和PCr/Pi比率.
- 乳酸释放最初增加,然后减少,酸化 (pH) 随着时间的推移显示了部分改善.
结论:
- 在持续性缺血期间,高能酸盐水平与血液流动和心脏功能相关.
- 乳酸盐的产生和酸性转化被部分缓解,这支持了减少能量需求有助于肌肉心脏保存的假设.
- 这些发现表明,减少能量需求有助于减少冬眠心肌缺血.
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