不同剪切应力对内皮细胞表面SR-B1 mRNA表达影响的实验研究  

The Study of the Influence of Different Shear Stress on the mRNA Expression of Scavenger Receptor Class B Type1 in Endothelial Cells

作　　者：于风旭[1] 张英[2] 凌生林[1] 石应康[3] 廖斌[1] 吴江[4] 

机构地区：[1]泸州医学院附属医院心胸外科,泸州646000 [2]泸州医学院附属医院麻醉科,泸州646000 [3]四川大学华西医院心胸外科,成都610041 [4]四川大学华西基础医学与法医学院生物医学工程实验室,成都610041

出　　处：《生物医学工程学杂志》2011年第1期81-85,120,共6页Journal of Biomedical Engineering

基　　金：四川省卫生厅基金资助项目(20097464);四川省教育厅基金资助项目(2007730)

摘　　要：研究不同剪切应力作用下,血管内皮细胞表面高密度脂蛋白(HDL)的特异性B族1型清道夫受体(SR-B1)mRNA的表达水平。采用第2～4代体外培养人脐静脉血管内皮细胞(HUVEC)。静态条件下未施加剪切应力培养组为对照组;实验组分为为低剪切应力组(4.2 dyne/cm2)、中等剪切应力组(8.4 dyne/cm2)和高剪切应力组(15dyne/cm2)。剪切应力加载时间分别为为1、2、4、8 h。剪切应力加载后收获细胞提取总RNA,并进行半定量RT-PCR测定脂蛋白受体SR-B1的mRNA表达。结果表明,在低剪切应力组刺激后,与对照组比较,SR-B1 mRNA表达随时间延长明显减弱,在8 h达低谷。在中等剪切应力组,随着作用时间的增加,自1～8 h,SR-B1 mRNA表达呈逐渐增加趋势,与对照组相比,自作用2 h后即出现显著差异;高剪切应力组,随着作用时间的增加,SR-B1 mRNA表达逐渐增加,至4 h达到峰值,然后维持在一个较高水平的平台上,与对照组相比,自作用1 h开始即有统计学差异。由此推断低剪切应力的内皮细胞损伤性机制可能为:通过下调SR-B1受体的表达,降低胆固醇的逆转运及其介导的内皮细胞保护作用,增加血管动脉粥样硬化发生的几率;而生理性高剪切应力的保护性机制与此正好相反。The present paper is to research the expression level of the mRNA of scavenger receptor class B type 1— receptor of high-density lipoprotein in endothelial cells after being treated by different shear stress.The second to fourth generations of the cultured human umbilical vein endothelial cells（HUVECs） were used in the experiment.The cells were divided into two groups.The first group was the control group which was not dealt with shear stress;the second group was the experimental group which concluded low shear stress group（4.2dyne/cm2）,moderate shear stress group（8.4dyne/cm2） and high shear stress group（15dyne/cm2）. The load time was 1h、2h、4h and 8h,respectively.Harvesting the cells and extracting total RNA after being treated by different shear stresses,the expression level of the SR-B1 mRNA was detected by semi-quantitative RT-PCR technic.It was found that the expression of SR-B1 mRNA became weaker and weaker compared to the control group when it was stimulated continuously by the low shear stress,the lowest expression of SR-B1 mRNA appeared at 8h.In the moderate shear stress group,the expression of SR-B1 mRNA increased obviously.Compared to the control group,there was significant difference after being treated with 2h.In the high shear stress group,the expression of SR-B1 mRNA increased immediately when it was stimulated by the shear stress.And the expression of SR-B1 mRNA arrived peak value at 4h.Compared to the control group,there was significant difference after being treated for 1h.It was concluded that the harmful mechanism of the low shear stress is that it can increase the incidence of the atherosclerosis by reducing the reverse cholesterol transport and endothelial protection through decreasing the expression of the SR-B1.Otherwise,the high shear stress prevent the genesis of atherosclerosis by the contrary mechanism.

关 键 词：剪切应力 B族1型清道夫受体 动脉粥样硬化 脐静脉内皮细胞 

分 类 号：R318.01[医药卫生—生物医学工程]