振荡切应力在运动定量调控颈总动脉内皮功能中的作用

Blood-flow-induced oscillatory shear stress is involved in regulation of the common carotid artery endothelial function by exercise training. Cell experiments in vitro at micro-level and exercise-intervention experiments in vivo at macro-level are combined to investigate the roles of oscillatory shear stress with different characteristics in quantitative regulation of the common carotid artery endothelial function by exercise trainings. At micro-level, the effects of oscillatory shear stress with different characteristics on vasoactive substances NO and ET-1 release from vascular endothelial cells cultured in vitro are investigated to understand the advantageous characteristics of oscillatory shear stress for vasodilation. At macro-level, the quantitative relationship among different exercise trainings, different oscillatory shear stress and the endothelial functions in the common carotid arteries of healthy male and female volunteers with different ages are investigated to seek the best exercise training method to generate the beneficial oscillatory shear stress for the endothelial function of the common carotid arteries. These investigations not only help to deeply understand the hemodynamic and biological mechanisms to prevent and treat cerebrovascular diseases by exercise trainings, but also provide a methodology base for regulation of cerebrovascular function by exercise-induced hemodynamics, which are of clinic values for the early diagnosis, prediction and treatment of cerebrovascular diseases.

血流引起的振荡切应力参与运动对颈总动脉内皮功能的调控。本项目将微观层次的离体细胞实验和宏观层次的在体运动干涉实验相结合探讨不同特征的振荡切应力在运动定量调控颈总动脉内皮功能中的作用。在微观层次，研究不同特征的振荡切应力对离体培养的血管内皮细胞分泌血管活性物质NO和ET-1的影响，探寻有利于血管舒张功能的振荡切应力特征；在宏观层次，以不同性别、不同年龄段的健康人群作为研究对象，研究不同的运动训练、颈总动脉振荡切应力和内皮功能三者之间的定量关系，寻找在颈总动脉产生对内皮功能有益的振荡切应力的最佳运动训练方法。这些工作不仅有助于深入理解运动预防和治疗脑血管疾病的血液动力学和生物学机制，而且还能为通过运动干涉血液动力学特性调控脑血管功能提供一种方法学基础。对于早期诊断、预防和治疗脑血管疾病，降低脑血管疾病的发病率，具有一定的临床应用价值。

血液脉动流产生的壁面剪切力参与运动对颈总动脉内皮功能的调控。本项目将宏观层次的在体运动干涉实验与微观层次的离体细胞实验相结合探究不同脉动特征的壁面剪切力在运动调控颈总动脉内皮功能中的作用。在宏观层次，分别研究了急性运动干预，长期运动干预，以及急性与长期结合的运动干预对颈总动脉硬度以及血流动力学参数的影响；在微观层次，通过设计和搭建能够近似模拟运动前后颈总动脉处血流剪切力环境的平行平板流动腔及其外围系统，研究了不同强度运动所引起的频率及幅值变化的壁面剪切力对内皮细胞中活性氧类（ROS）以及一氧化氮（NO）分泌的影响。宏观的在体研究以及微观的离体细胞实验结果均表明，中等强度的有氧运动可以作为改善颈总动脉内皮功能的较为有益的运动方式。本项目的研究工作不仅能够为运动方式的选择提供参考及理论依据，而且能够进一步研究运动对动脉内皮功能改善的分子生物学机制提供有效的研究平台。