Goldsmith H L
Thromb Diath Haemorrh. 1974 Sep 30;32(1):35-48.
Platelet thrombi have been observed at bifurcations, constrictions and stenoses in the arterial tree where flow separation with accompanying vortex formation can occur. Hence, studies of the flow behavior of human blood cells in models of a vessel obstruction and a sudden expansion of a vessel lumen were carried out. These showed that the particles were subjected to first high, and then much lower shear stresses as they entered the vortices where the environment appeared favorable for the formation of aggregates. The effects of high and variable shear stress on the release reaction and aggregation of platelets were therefore studied using cells labeled with C14-Serotonin suspended in Tyrodes-albumin undergoing oscillatory tube flow for 20 min at 37degrees C. There was no significant release of serotonin due to flow alone, but the thrombin-induced release of C14-activity was appreciably greater in suspensions subjected to shear rates greater than 2000 sec-1 than in control suspensions which had been incubated at rest. The synergistic effects of the shear flow were also noted in the presence of adrenaline, which increased the release reaction, and when [Ca++] was raised above the physiological level or acetyl salicylic acid added, which inhibited the release of serotonin.
在动脉树的分叉处、狭窄处和缩窄处观察到血小板血栓，这些部位可能会出现流动分离并伴有涡流形成。因此，开展了关于人体血细胞在血管阻塞模型和血管腔突然扩张模型中的流动行为的研究。这些研究表明，当颗粒进入涡流时，首先会受到高剪切应力，然后剪切应力会低得多，而涡流中的环境似乎有利于聚集体的形成。因此，使用悬浮在泰罗德白蛋白溶液中并用C14 - 血清素标记的细胞，在37℃下进行20分钟的振荡管流，研究了高剪切应力和可变剪切应力对血小板释放反应和聚集的影响。仅因流动不会导致血清素显著释放，但在剪切速率大于2000秒-1的悬浮液中，凝血酶诱导的C14活性释放明显大于在静止状态下孵育的对照悬浮液。在存在肾上腺素（其会增加释放反应）以及当[Ca++]升高到生理水平以上或添加乙酰水杨酸（其会抑制血清素释放）时，也注意到了剪切流的协同作用。
