School of Mathematics, Jilin University, Qianjin Ave. 2699, Changchun, 130012, China.
Department of Mechanical Engineering, National University of Singapore, Singapore, 117576, Singapore.
Biomech Model Mechanobiol. 2020 Jun;19(3):943-955. doi: 10.1007/s10237-019-01262-x. Epub 2019 Nov 21.
Thrombus formation is a complex, dynamic and multistep process, involving biochemical reactions, mechanical stimulation, hemodynamics, and so on. In this study, we concentrate on its two crucial steps: (i) platelets adhered to a vessel wall, or simply platelet adhesion, and (ii) platelets clumping and arrested to the adherent platelets, named platelet aggregation. We report the first direct simulation of three modes of platelet adhesion, detachment, rolling adhesion and firm adhesion, as well as the formation, disintegration, arrestment and consolidation of platelet plugs. The results show that the bond dissociation in the detachment mode is mainly attributed to a high probability of rupturing bonds, such that any existing bond can be quickly ruptured and all bonds would be completely broken. In the rolling adhesion, however, it is mainly attributed to the strong traction from the shear flow or erythrocytes, causing that the bonds are ruptured at the trailing edge of the platelet. The erythrocytes play an important role in platelet activities, such as the formation, disintegration, arrestment and consolidation of platelet plugs. They exert an aggregate force on platelets, a repulsion at a near distance but an attraction at a far distance to the platelets. This aggregate force can promote platelets to form a plug and/or bring along a part of a platelet plug causing its disintegration. It also greatly influences the arrestment and consolidation of platelet plugs, together with the adhesive force from the thrombus.
血栓形成是一个复杂、动态和多步骤的过程，涉及生化反应、机械刺激、血液动力学等。在本研究中，我们集中研究其两个关键步骤：（i）血小板黏附于血管壁，或简单地说血小板黏附，以及（ii）血小板聚集和黏附于已黏附的血小板，称为血小板聚集。我们报告了三种血小板黏附模式的首次直接模拟，包括黏附、脱离、滚动黏附和牢固黏附，以及血小板栓子的形成、崩解、阻滞和巩固。结果表明，在脱离模式下的键解离主要归因于高键断裂概率，使得任何现有键都可以迅速断裂，所有键都会完全断裂。然而，在滚动黏附中，它主要归因于剪切流或红细胞的强大牵引力，导致在血小板的尾缘处键断裂。红细胞在血小板的活动中起着重要作用，如血小板栓子的形成、崩解、阻滞和巩固。它们对血小板施加一个聚集力，在近距离时排斥，在远距离时吸引血小板。这种聚集力可以促进血小板形成栓子和/或带动一部分血小板栓子导致其崩解。它还极大地影响血小板栓子的阻滞和巩固，与血栓形成的黏附力一起。
