研究目的：运用生物力学检测技术，引进新的评价指标，丰富AS小鼠血管力学特性评价体系，并应用于有氧运动对AS小鼠主动脉血管力学特性的影响研究过程中。为进一步探究动脉粥硬样病理过程的力学特点，探讨有氧运动改善AS小鼠主动脉力学特性的可能机制与方向，完善心血管疾病防治方法，提供力学生物学的实验数据支撑。
研究方法：雄性ApoE-/-小鼠和C57小鼠各24只，分别喂养高脂和普通饲料，随机等分为运动组和对照组，进行8周有氧运动干预。测量小鼠体重、血压和糖耐量后取材。利用油红O染色判断建模效果，测量血脂水平，透射电镜下观察内皮细胞形态，立体激光扫描获得血管壁三维立体结构图像，光镜下测量主动脉张开角，利用微纳米拉伸系统和原子力显微技术获得主动脉轴向和法向的弹性模量。
研究结果：（1）ApoE-/-小鼠+高脂饲料喂养的方式进行AS小鼠建模成功。干预结束后，与NC组相比，NE组体重减轻（p≤0.01），AC组体重增加（p≤0.01）；与AC组相比，AE组体重减轻（p≤0.05）。（2）与NC组相比，AC组HR（p≤0.01）、SBP（p≤0.01）、DBP（p≤0.05）均显著升高；与AC组相比，AE组HR（p≤0.01）、SBP（p≤0.05）显著下降，DBP下降，但结果不具有显著性。（3）与NC组相比，NE组HDL（p≤0.05）升高；AC组空腹血糖值（p≤0.05）、AUC（p≤0.01）、TC（p≤0.01）、TG（p≤0.01）、LDL（p≤0.05）均显著升高，HDL（p≤0.01）显著降低。与AC组相比，AE组空腹血糖值（p≤0.05）、AUC（p≤0.05）、TC（p≤0.05）、LDL（p≤0.05）均显著降低，HDL（p≤0.05）显著升高。（4）与NC组相比，NE组血管壁略有增厚，组织结构分布更加均匀致密；AC组小鼠内皮细胞变形、脱落，内膜不平整，血管壁增厚，分层模糊，组织结构分布不均匀。与AC组相比，AE组内皮损伤改善，内膜较平整光滑，管壁厚度整体减小。（5）与NC组相比，NE组和AC组血管壁法向弹性模量显著增大（p≤0.01），且AC组增量幅度大，分布离散程度高；与AC组相比，AE组血管壁法向弹性模量显著减小（p≤0.01），分布集中程度高。（6）与NC组相比，AC组张开角显著增大（p≤0.05）；与AC组相比，AE组张开角显著减小（p≤0.05）。
研究结论：（1）有氧运动可以降低AS小鼠体重，改善心血管功能，提高糖脂代谢水平。维持内皮和血管壁正常结构，抑制组织增生。在正常小鼠预防AS过程中也起到积极作用，结合饮食控制效果可能会更好。（2）AS过程伴随主动脉血管壁病理性重建，血管壁非均匀性生长，血管张开角增大，可能与AS小鼠生理功能紊乱有关。有氧运动可以改善AS状态时的血管壁力学环境，缓解AS血管病理性重建过程，并在一定范围内促进健康血管良性重建，结合饮食控制效果可能会更好。（3）AS小鼠主动脉血管壁法向弹性模量非均匀性增大，弹性大幅度减小，且变化不均匀。有氧运动可以抑制AS血管结构功能恶化造成的力学特性变化，改善正常小鼠血管壁力学特性，为防止运动状态时血管过度扩张提供保障，结合饮食控制效果可能会更好。

Objective: The biomechanical detection technology was used to introduce new evaluation indexes to enrich the evaluation system of vascular mechanical properties of AS mice, and the system was applied to the study of the effect of aerobic exercise on vascular mechanical properties of AS mice.In order to further explore the mechanical properties of the pathological process of arterial porridge, explore the possible mechanism and direction of aerobic exercise to improve the mechanical properties of the aorta of AS mice, improve the prevention and treatment methods of cardiovascular diseases, and provide experimental data support of mechanical biology.
Methods: 24 male ApoE-/- mice and C57 mice were fed with high fat and normal diet, respectively. They were randomly divided into the exercise group and the control group for 8 weeks of aerobic exercise intervention. Body weight, blood pressure and glucose tolerance of the mice were measured. Oil red O staining was used to determine the modeling effect, blood lipid level was measured, the morphology of endothelial cells was observed under transmission electron microscopy, stereoscopic laser scanning was used to obtain the three-dimensional structure image of the vascular wall, the opening angle of the aorta was measured under light microscope, and the axial and normal elastic modulus of the aorta were obtained by using the micro-nano tensile system and atomic force microscopy.
Results: (1) ApoE-/- mice + high-fat feed was successfully modeled in AS mice. After the intervention, compared with the NC group, the NE group lost weight （p≤0.01） and the AC group gained weight （p≤0.01）. Compared with the AC group, the AE group lost weight （p≤0.05）. (2) Compared with the NC group, HR (p≤0.01), SBP (p≤0.01) and DBP (p≤0.05) in the AC group increased significantly. Compared with the AC group, HR (p≤0.01) and SBP (p≤0.05) in the AE group decreased significantly, and DBP decreased, but the results were not significant. (3) Compared with NC group, HDL (p≤0.05) increased in NE group. Fasting blood glucose (p≤0.05), AUC (p≤0.01), TC (p≤0.01), TG (p≤0.01), and LDL (p≤0.05) were all significantly increased in the AC group, while HDL (p≤0.01) was significantly decreased. Compared with the AC group, the fasting blood glucose value (p≤0.05), AUC (p≤0.05), TC (p≤0.05) and LDL (p≤0.05) in the AE group were all significantly reduced, while HDL (p≤0.05) was significantly increased. (4) Compared with the NC group, the vascular wall of the NE group was slightly thicker and the tissue structure was more uniform and dense. In the AC group, the endothelial cells were deformed and exfoliated, the intima was uneven, the vascular wall was thickened, the stratification was fuzzy, and the tissue structure distribution was uneven. Compared with the AC group, the endothelial injury was improved in the AE group, the intima was relatively flat and smooth, and the overall thickness of the tube wall was reduced. (5) Compared with the NC group, the normal elastic modulus of vessel wall in the NE group and the AC group increased significantly (p≤0.01), and the AC group had a large increment range and a high dispersion degree. Compared with the AC group, the normal elastic modulus of vascular wall in the AE group was significantly reduced (p≤0.01) and the distribution concentration was high. (6) Compared with the NC group, the opening Angle of AC group increased significantly (p≤0.05). Compared with AC group, the opening Angle of AE group was significantly reduced (p≤0.05).
Conclusion: (1) Aerobic exercise can reduce the weight of AS mice, improve cardiovascular function, and improve the level of glucose and lipid metabolism. Maintain the normal structure of endothelium and vascular wall, and inhibit tissue proliferation. It also plays a positive role in the prevention of AS in normal mice, and the combined effect of diet control may be better. (2) AS process is accompanied by pathological reconstruction of aortic vascular wall, the vascular wall grows inhomogeneous, and the vascular opening Angle increases, which may be related to the physiological dysfunction of AS mice. Aerobic exercise can improve the mechanical environment of vascular wall in the state of AS, relieve the rational remodeling process of AS vascular disease, and promote the benign remodeling of healthy blood vessels within a certain range. Combined with diet control, the effect may be better. (3) the inhomogeneity of the normal elastic modulus of aortic wall in AS mice increased, while the elasticity decreased significantly, and the change was not uniform. Aerobic exercise can inhibit the changes in mechanical properties caused by the deterioration of vascular structure and function of AS, improve the mechanical properties of blood vessel walls in normal mice, and provide a guarantee to prevent the excessive dilation of blood vessels during exercise. Combined with diet control, the effect may be better.