Zhu Hui, Zhang Ji, Shih Jessica, Lopez-Bertoni Federico, Hagaman John R, Maeda Nobuyo, Friedman Morton H
Department of Biomedical Engineering, Duke University, Durham, NC 27708-0281.
J Biomech Eng. 2009 Dec;131(12):121005. doi: 10.1115/1.4000168.
Atherosclerotic plaques are distributed differently in the aortic arches of C57BL/6 (B6) and 129/SvEv (129) apolipoprotein E (apoE)-deficient mice. It is now recognized that hemodynamic wall shear stress (WSS) plays an important role in the localization of atherosclerotic development. Since the blood flow field in the vessel is modulated by the vascular geometry, we quantitatively examined the difference in the aortic arch geometry and hemodynamic WSS between the two corresponding wild-type mouse strains. The three-dimensional (3D) geometry of 14 murine aortic arches, seven from each strain, was characterized using casts and stereo microscopic imaging. Based on the geometry of each cast, an average 3D geometry of the aortic arch for each mouse strain was obtained, and computational fluid dynamic calculations were performed in the two average aortic arches. Many geometric features, including aortic arch shape, vessel diameter, and branch locations, were significantly different at p<0.05 between the two mouse strains. Lower shear stress was found at the inner curvature of the aortic arch in the 129 strain, corresponding to greater involvement in the corresponding apoE-deficient mice relative to the B6 strain. These results support the notion that heritable features of arterial geometry can contribute to individual differences in local susceptibility to arterial disease.
动脉粥样硬化斑块在C57BL/6（B6）和129/SvEv（129）载脂蛋白E（apoE）缺陷小鼠的主动脉弓中分布不同。现在人们认识到，血流动力学壁面剪应力（WSS）在动脉粥样硬化发展的定位中起重要作用。由于血管中的血流场受血管几何形状调节，我们定量研究了两种相应野生型小鼠品系之间主动脉弓几何形状和血流动力学WSS的差异。使用铸型和立体显微镜成像对14个小鼠主动脉弓的三维（3D）几何形状进行了表征，每个品系各7个。根据每个铸型的几何形状，获得了每个小鼠品系主动脉弓的平均3D几何形状，并在两个平均主动脉弓中进行了计算流体动力学计算。在两种小鼠品系之间，许多几何特征，包括主动脉弓形状、血管直径和分支位置，在p<0.05时存在显著差异。在129品系的主动脉弓内曲率处发现较低的剪应力，这与相应的apoE缺陷小鼠相对于B6品系的受累程度更高相对应。这些结果支持了这样一种观点，即动脉几何形状的遗传特征可能导致个体对动脉疾病局部易感性的差异。
