Experimental determination of wall shear rate in canine carotid arteries perfused in vitro.
Experimental determination of wall shear rate in canine carotid arteries perfused in vitro.
复制标题
体外灌注犬颈动脉壁剪切率的实验测定。
DOI：
10.1016/0021-9290(89)90216-9
复制
发表时间：
1989
影响因子：
2.4
通讯作者：
Borovetz,HS
中科院分区：
文献类型：
--
作者：
Johnson,GA;Hung,TK;Brant,AM;Borovetz,HS
采用Hung （Tsai and Hung, 1984）的数学模型来测定体外灌注犬颈动脉的壁剪切速率。将可变形容器内脉动流动的模型方程与动压降、流量、容器半径和径向壁面运动的实验数据相结合。对于暴露于“正常血压”血流动力学、“高血压”模拟和故意改变血管壁顺应性的灌注的血管，可以获得诸如速度剖面和壁剪切等衍生量。我们的研究结果表明，壁面剪切随血流动力学环境的变化而显著变化。还论证了容器半径与流速对壁面剪切发展的影响。在“高压”模拟中发现对流过程与壁面剪切的大小相关。目前的研究结果和补充发表的数据可以解释，至少部分地，血管壁运输和内皮细胞生物学的变化，我们观察到作为血流动力学环境的功能。例如，我们已经证明，犬类颈动脉暴露于“高血压”（与“正常”）血液动力学与脂蛋白（LDL）进入内膜和腔内介质的通量增加有关。另一方面，壁顺应性的改变深刻地影响内皮的形状、取向和细胞骨架排列。
The mathematical model of Hung (Tsai and Hung, 1984) is empolyed to determine the wall shear rate acting on canine carotid arteries perfusedin vitro. Model equations for pulsatile flow in a deformable vessel are coupled with experimental data of dynamic pressure drop, flow rate, vessel radius and radial wall motion. Derived quantities, e.g. velocity profiles and wall shear, are obtained for vessels exposed to ‘normotensive’ hemodynamics, ‘hypertension’ simulations and perfusions in which the compliance of the vessel wall is deliberately altered. Our results indicate that wall shear varies markedly as a function of the hemodynamic environment. The effects of vessel radius vs flow rate on the development of wall shear are also demonstrated. It is found that convective processes correlate with the magnitude of wall shear in the ‘hypertension’ simulations.The present findings and complementary published data may explain, at least in part, the variations in vessel wall transport and endothelial cell biology we observe as a function of the hemodynamic environment. For example we have documented that the exposure of canine carotids to ‘hypertensive’ (vs ‘normotensive’) hemodynamics is associated with an increased flux of lipoproteins (LDL) into the intima and luminal media. Alternations in wall compliance, on the other hand, profoundly influence endothelial shape, orientation and cytoskeletal array.