流体切应力对年轻和老年大鼠肠系膜微动脉eNOS表达和NO释放量的影响

摘要

Objective To observe the roles of the expression of endothelial nitric oxide synthase (eNOS) and the release of nitric oxide (NO) mediated by fluid shear stress on vascular aging in young and aging rats. Methods Models of high flow (HF) and normal flow (NF) of micro- arterial perfusion were established by selective ligation of secondorder mesenteric micro - arteries in vivo in young (6 months old) and aging (24 months old) rats to produce different fluid shear stress. Three weeks after operation, the arteries were isolated under a dissecting microscope to determine the release of NO and the expression of eNOS. Results With intravascular fluid shear stress elevated, the expression of eNOS protein and mRNA were upregulated significantly, and the production of NO increased. Conclusion Increased fluid shear stress of blood vessels can improve the micro - arterial functions of young and aging rats by changing the expression of eNOS and the release of NO.%目的 观察流体切应力引起的年轻和老年大鼠肠系膜微动脉内皮型一氧化氮合酶(eNOS)表达和一氧化氮(NO)释放量改变对血管老化的作用. 方法 采用选择性结扎年轻(6月龄)和老年(24月龄)大鼠肠系膜微动脉产生不同的流体切应力,制备正常和高流体切应力(NF和HF)微动脉灌流模型,术后3周分离血管测定年轻和老年大鼠NF和HF肠系膜微动脉NO的释放量及其限速酶eNOS mRNA和总蛋白及磷酸化蛋白的表达.结果 增加流体切应力后,血管eNOS mRNA和蛋白质表达水平增加,NO释放量增多.结论 流体切应力可以改变eNOS的表达及NO的释放量,从而改善老年大鼠微动脉的功能.