From the Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, China.
ASAIO J. 2011 Nov-Dec;57(6):487-94. doi: 10.1097/MAT.0b013e318233b5ed.
To test the hypothesis that the mechanotransduction of flow-induced shear stress on endothelial cells (ECs) might be triggered by the total torque transmitted from the glycocalyx fibers to the ECs rather than by the total shear force acting directly on the membrane of ECs, we formulated the arterial wall as a five-layer model and numerically investigated the effect of two types of damages to the endothelial glycocalyx layer (EGL) on the flow in the EGL and on the drag force and bending moment acting on the glycocalyx fibers. One type of damage was to alter the thickness of the EGL, and the other was to damage its integrity. The results revealed that almost all amount of the shear stress acting on ECs was transmitted to the cells by the EGL and that the flow-induced shear stress acting directly on the cell membrane was negligibly small. In addition, the total force transmitted from the glycocalyx fibers to the cell membrane in the forms of drag force was hardly affected by the damages to the EGL. However, such damages could significantly influence the total torque at the roots of the EGL fibers. In conclusion, the mechanotransduction of shear stress by the EGL might be torque determined rather than force determined.
为了验证以下假设，即内皮细胞（EC）的流致切应力的机械转导可能是由糖萼纤维传递到 EC 的总扭矩引发的，而不是由直接作用于 EC 膜的总剪切力引发的，我们将动脉壁构建为五层模型，并数值研究了两种类型的内皮糖萼层（EGL）损伤对 EGL 内流以及对糖萼纤维上的阻力和弯矩的影响。一种损伤是改变 EGL 的厚度，另一种是破坏其完整性。结果表明，几乎所有作用于 EC 的切应力都通过 EGL 传递到细胞，而直接作用于细胞膜的流致切应力可以忽略不计。此外，以阻力形式从糖萼纤维传递到细胞膜的总力几乎不受 EGL 损伤的影响。然而，这种损伤会显著影响糖萼纤维根部的总扭矩。总之，EGL 的切应力机械转导可能是由扭矩决定的，而不是由力决定的。
