在冠状动脉微循环中α1-和α2-上腺素受体的功能分布
1Department of Medical Physiology, Texas A&M University, College Station.
Circulation
|November 1, 1991
概括
冠状动脉小动脉逃脱阿尔法-上腺缩时,血管运动的音调是完整的,但在hyperfusion变得敏感. 阿尔法-1受体广泛存在,而阿尔法-2受体主要存在于动脉小管中.
科学领域:
- 心血管生理学心血管生理学
- 上腺素受体药理学 上腺素受体药理学
背景情况:
- 研究冠状动脉微循环中α1-和α2-上腺体受体的分布和功能对于理解血液流量调节至关重要.
- 之前的研究已经提供了洞察力,但仍需要在上心冠状动脉微血管内进行详细的功能映射.
研究的目的:
- 确定心上冠状动脉微循环中的α1-和α2-上腺素受体的功能分布.
- 阐明这些受体在不同的生理条件下对冠状动脉和动脉小板产生不同的影响.
主要方法:
- 在一个跳动的心脏模型中,对选择性α1-上腺激动剂 (乙烯) 和α2-上腺激动剂 (BHT-933) 进行冠状动脉内注射.
- 冠状动脉微血管直径的测量在完整的血管运动音调和冠状动脉低的条件下.
- 使用选择性α1- (普拉佐辛) 和α2-上腺素 (SKF 104078) 抗剂的激素选择性的证实.
主要成果:
- 烯会导致小冠状动脉 (血管>100微米) 的收缩,但不会导致动脉小动脉 (<100微米) 保持完整的血管运动度.
- 在低 perfusion 期间,基缩了小动脉和动脉小动脉.
- 在低 perfusion 期间,BHT-933 选择性地和显著地收缩了动脉小管,在正常条件下没有效果.
结论:
- 冠状动脉小动脉表现出"自调节性逃逸"从α-上腺体收缩当血管运动的音调是完整的,不像冠状动脉.
- 在低输液过程中,α1-和α2-上腺激动剂都显著收缩了冠状动脉小动脉.
- 阿尔法-2受体似乎主要位于动脉小管中,而阿尔法-1受体在冠状动脉微循环中分布更广泛.
相关概念视频
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