【摘要】 目的利用超声显像检测临床异丙酚深度镇静状态时肱动脉血流介导的内皮依赖性舒张功能(EDD)和硝酸甘油介导的非内皮依赖性舒张功能(EID),并结合实验室检测镇静前后血中一氧化氮(NO)、血管性血友病因子(vWF)的含量变化,初步探讨异丙酚影响血管内皮舒张功能的机制。方法选择30例志愿者,分别在清醒和异丙酚深度镇静状态下,用高频探头,以彩色多普勒超声显像法测定反应性充血和静脉注射硝酸甘油时肱动脉内径、血流量的变化;所有受试对象均在清醒状态下及异丙酚深度镇静状态下取前臂肘静脉血6m l,分别采用硝酸还原酶法及酶联免疫吸附双抗体夹心法(ELISA)测定NO及vWF含量,同时记录镇静前后心率和血压的变化。结果在异丙酚深度镇静状态下,受试者血压、血流和硝酸甘油介导的肱动脉内径变化百分比、加压及注射硝酸甘油引起的肱动脉局部血流量的增加以及血中NO含量均较清醒时明显下降(P<0.05),而镇静前后vWF含量的变化差异无统计学意义(P>0.05)。结论异丙酚具有循环抑制作用,同时它通过抑制NO的生成,使体内NO水平下降,从而对内皮依赖性和非内皮依赖性的血管舒张功能均有抑制作用,NO起了第二信使的作用。更多还原

【Abstract】 Objective To test brachial artery endotheliumdependent vasodilation mediated by flow and endothelium-independent vasodilation mediated by nitroglycerin during clinical deep sedation with propofol by ultrasound imaging,and simultaneously,to study the mechanism of effects of propofol on serum NO levels and plasma von willebrand factor(vWF) levels before and after sedation.Methods Before and after propofol was injected,thirty normal subjects were examined by color doppler imaging to record blood pressure,volume of blood flow and variation of the brachial artery diameter at resting condition,during reactive hyperemia and after injecting nitroglycerin.In all subjects,6ml venous blood sample was taken at lucid and propofol-induced sedation conditions,we measured concentration of NO by nitrate reductase method and concentration of von willebrand factor(vWF) by ELISA.Results Blood pressure,concentration of NO,volume blood flow volume of brachial artery and variation of the brachial artery diameter mediated by folw and by nitroglycerin were lower at the propofol-induced sedation than that at lucid condition(P<0.05).There was no difference in plasma vWF levels between lucid and sedation conditions(P>0.05).Conclusion Endothelial-dependent and endothelial-independent vasodilation function are impaired at propofol-induced deep sedation.NO operated as secondary messenger.更多还原