上腺素增加了依赖于维勒布兰德因子的剪切诱导的血小板聚合
1Cardiopulmonary Division, School of Medicine, Keio University, Tokyo, Japan.
Circulation
|December 1, 1992
概括
在高剪切条件下,上腺素通过威尔布兰德因子 (vWF) 增强剪切诱导的血小板聚合 (SIPA). 这种相互作用对于理解狭窄动脉中的血块形成至关重要.
科学领域:
- 血液学 血液学 血液学
- 生物物理学的生物物理.
背景情况:
- 剪切诱导的血小板聚合 (SIPA) 是血液凝块形成 (血栓形成) 的关键因素.
- ·威尔布兰德因子 (vWF) 与血小板糖蛋白Ib (GP Ib) 结合,对于高剪力下的血小板聚合至关重要,例如在狭窄的动脉中发现的.
研究的目的:
- 为了澄清vWF依赖SIPA的生理意义.
- 在不同剪切条件下调查SIPA中上腺素,ADP和原等激动剂在SIPA中的作用.
主要方法:
- 分析了23名健康志愿者的血液样本.
- 使用修改后的圆板粘度计来测量SIPA的光传输.
- 上腺素,ADP和原对SIPA的影响在低 (12dne/cm2) 和高 (108dne/cm2) 的剪切力下进行了测试.
主要成果:
- 上腺素,ADP和原在低剪切时增强SIPA.
- 只有上腺素在高剪切时增强SIPA,将聚合从37.9%增加到59.7%.
- 一种α2-上腺素受体抗剂 (yohimbine) 阻断了上腺素的作用;一种抗vWF抗体 (NMC-4) 消除了高剪切SIPA.
结论:
- 上腺素作为主要激动剂,通过其特定受体增强vWF介导的SIPA.
- 这种机制在临床上具有重要意义,因为冠状动脉封闭通常在交感刺激期间发生在动脉样硬化血管中.
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