在运动期间,血清激素选择性地加重心下内脏缺血远程到冠状动脉狭窄
R J Bache1, R P Stark, D J Duncker
1Cardiovascular Division, University of Minnesota Medical School, Minneapolis 55455.
Circulation
|November 1, 1992
概括
血清激素通常会扩大冠状动脉,但在运动诱导的低输液过程中会收缩心下血管流. 这表明,血清激素可以选择性地增加心下内脏中对血液流动的抵抗力.
科学领域:
- 心血管生理学心血管生理学
- 药理学 药理学是指药理学的学科.
背景情况:
- 在心肌缺血期间,冠状动脉循环仍然对刺激做出反应.
- 血清素具有血管扩张和血管收缩的两种特性.
- 研究了它在低输血期间对冠状动脉循环的影响.
研究的目的:
- 为了检查血清素对冠状动脉循环的作用,远离静脉狭窄,在运动期间引起心肌缺血.
- 为了确定血清的双重性质是否会影响缺血条件下的血液流动分布.
主要方法:
- 七只长期使用仪器的狗在跑步机炼期间与冠状动脉狭窄进行了研究.
- 在注入血前和注入血期间,使用放射性微球测量了心肌血流量.
- 狭窄被调整以保持恒定的远距离冠状动脉压力.
主要成果:
- 在缩的运动期间,心肌血流量减少了45%,最显著的是心下内脏.
- 血清激素输注 (0.4-2.0微克/千克/分钟) 降低了心下流量,并倾向于增加心下流量,而不会改变远部压力.
- 在正常的动脉流入中,血会增加心下和心下血流.
结论:
- 在正常情况下,色胺扩大冠状动脉阻力血管,并增加了所有心肌层的流量.
- 在低输液过程中,血清素会导致心脏下部的血管扩张,但心脏下部的血管收缩.
- 血清似乎缩小了室内穿透动脉,选择性地增加了对心下内脏血流的抵抗力.
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