Liu Jian, Liu Ying, Bin Bi-yan, Li Mei-yu, Huang Rui-zhu, Wu Wei-lan, Yuan Ye, Bin Jian-ping
Department of Cardiology, Southern Medical University, Guangzhou, China.
Nan Fang Yi Ke Da Xue Xue Bao. 2011 Aug;31(8):1349-52.
To establish a mouse model of abdominal aorta stenosis and analyze the alterations in the arterial wall response to high and low shear stress.
Twenty mouse were randomized equally into 4 groups, including 3 test groups (1, 7 and 14 day groups) with surgically induced stenosis of the abdominal aorta, and a sham-operated group without stenosis. The hemodynamics and the internal diameter of the blood vessel were measured by color Doppler flow imaging. The wall shear stress was calculated by Poiseiulle hydrodynamics formula (τ(m)=η×4×V(m)/D). Pathological examination and immunohistochemistry were performed to observe the arterial morphological changes and the endothelial vascular cell adhesion molecule-1 (VCAM-1) expression. The intimal-media thickness of the aorta was measured and endothelial VCAM-1 expression analyzed quantitatively.
Regions of low and high flow shear stress were created upstream from the stenosis and within the stenosis, respectively. Compared with the sham-operated group, the mice with aorta stenosis showed gradually increased vascular intimal-media thickness and VCAM-1 expression intensity in the upstream aorta, but not within the regions of the stenosis.
Vascular remodeling may occur shortly after exposure to low shear stress, which plays a significant role in initiation and progression of the pathological process of atherosclerosis mediated by VCAM-1, whereas high shear stress may exert an anti-atherosclerotic effect.
建立小鼠腹主动脉狭窄模型，分析动脉壁对高、低剪切应力反应的变化。
将20只小鼠随机均分为4组，包括3个试验组（1天、7天和14天组），通过手术诱导腹主动脉狭窄，以及1个假手术组（无狭窄）。采用彩色多普勒血流成像测量血流动力学和血管内径。通过泊肃叶流体动力学公式（τ(m)=η×4×V(m)/D）计算壁面剪切应力。进行病理检查和免疫组织化学，观察动脉形态变化及内皮血管细胞黏附分子-1（VCAM-1）表达。测量主动脉内膜中层厚度并定量分析内皮VCAM-1表达。
分别在狭窄上游和狭窄部位形成低、高血流剪切应力区域。与假手术组相比，腹主动脉狭窄小鼠的上游主动脉血管内膜中层厚度和VCAM-1表达强度逐渐增加，但在狭窄区域内未出现这种情况。
暴露于低剪切应力后不久可能发生血管重塑，这在由VCAM-1介导的动脉粥样硬化病理过程的起始和进展中起重要作用，而高剪切应力可能发挥抗动脉粥样硬化作用。
