Gleason Rudolph L, Humphrey Jay D
Department of Biomedical Engineering and M.E. DeBakey Institute, Texas A&M University, 337 Zachry Engineering Center, TAMU 3120, College Station, 77843, USA.
Math Med Biol. 2005 Dec;22(4):347-69. doi: 10.1093/imammb/dqi014.
Soft tissue growth and remodelling (G&R) are achieved through highly complex, temporally regulated mechanisms that lead to the adaptation of structurally significant cells and extracellular matrix proteins. Herein we present a constrained mixture model to describe vascular adaptations in response to large perturbations in luminal flow rate, transmural pressure and axial extension. In the associated simulations, G&R occur in evolving loaded (i.e. current) configurations. Although several hypotheses are employed with regard to vasoregulatory mechanisms and rates of growth and turnover of individual constituents, the main hypothesis is that each structural constituent is produced within a range of homeostatic stresses (or stretches). As a result, although material that was produced in one configuration may have the same mechanical behaviour as that produced in another configuration, these materials will possess different natural configurations and contribute a different structural response to the mixture. Our simulations illustrate how, by simply evolving the reference states of individual constituents, blood vessels can adapt their structure and function to restore wall stresses.
软组织生长与重塑（G&R）是通过高度复杂、受时间调节的机制实现的，这些机制导致具有结构重要性的细胞和细胞外基质蛋白发生适应性变化。在此，我们提出一种约束混合模型，以描述血管对管腔流速、跨壁压力和轴向伸展的大幅扰动所做出的适应性变化。在相关模拟中，G&R发生在不断演变的加载（即当前）构型中。尽管关于血管调节机制以及各个成分的生长和更新速率采用了几种假设，但主要假设是每个结构成分都是在一系列稳态应力（或拉伸）范围内产生的。因此，尽管在一种构型中产生的材料可能与在另一种构型中产生的材料具有相同的力学行为，但这些材料将具有不同的自然构型，并对混合物产生不同的结构响应。我们的模拟说明了通过简单地演变各个成分的参考状态，血管如何能够调整其结构和功能以恢复壁应力。
