Development of Measuring System of Endothelium-Derived Relaxing Factor(NO)and Vascular Luminal Shear Stress

1.分离的大鼠心脏：使用NO微电极（100 μ m; 1 μ A（] SY.ap.）[1.5 nM NO]。冠状动脉灌流液中NO浓度随灌流压的升高而升高（47（±）SY. [)6在40 cm H<@D22@> D2 O时，pA为69（±）SY。[)10在70 cm H <@D22@> D2 O时的pA，99（±）SY. [)17在100 cm H <@D22@> D2 O时的pA）。缺血1分钟后，再灌注期间观察到NO浓度的短暂峰值，缺血10分钟后，观察到最初出现短暂的小峰值，随后逐渐增加（达到假稳定值）（22（± SD））。[)3 pA 1 min vs 124（± SD）。[)17 pA，10 min）。这些结果似乎反映了缺血过程中积累的NO的洗脱以及再灌注过程中切应力的增加作用.人工血管：两种类型的人工血管（Terumo的PF-V和戈尔的ePTFE;均为10 cm长） ...更多信息 植入狗的股动脉。一段时间后，分离每个血管，并测量内皮的NO产生。1 mM L-精氨酸和100 μ M L-NA灌注之间测得的NO电流的差异如下：2周后（PF-V：52 pA，49 pA），1个月后（PF-V：45 pA，ePTFE：233 pA），12个月后（无显著变化），和13个月后（无显著变化）。这些结果表明，在每个血管的管腔侧形成的新生内膜在短期植入后具有产生NO的能力，但在长时间（约1年）后，内皮认识到NO产生的生理功能是不必要的，因此可能导致NO合酶活性和/或NO合酶数量的降低。从内皮产生的NO与抗血栓形成直接相关，因此在这方面，新生内膜的抗血栓形成能力可能在长时间后减弱。少

1.Isolated Rat Hearts : NO concentration in the coronary perfusate ejected from the pulmonary artery of isolated rat hearts(perfused in Langendorff mode) was measured using an NO microelectrode (100 mum ; 1 pA (]SY.apprxeq.[) 1.5 nM NO). NO concentration in the coronary perfusate increased with increasing perfusion pressure (47(]SY.+-。[)6 pA at 40cm H<@D22@>D2O,69(]SY.+-。[)10 pA at 70 cmH<@D22@>D2O,99(]SY.+-。[)17 pA at 100 cmH<@D22@>D2O). After 1-min ischemia, a transient peak of NO concentration was observed during reperfusion, and after 10-min ischemia, a transient small peak appeared initially followed by a gradual increase (reaching a peudo-steady value)was observed (22(]SY.+-。[)3 pA for 1 min vs 124(]SY.+-。[)17 pA for 10 min). These results seem to reflect the washout of accumulated NO during ischemia as well as the increasing effect of shear stress during reperfusion.2. Artificial Vessels : Two types of artificial vessels (PF-V of Terumo and ePTFE of Gore ; both 10 cm long) were … More implanted in dogs by connecting to the femoral arteries. After a certain period, each vessel was isolated, and NO production from the endothelium was measured. The differences of measured NO currents between 1 mM L-arginine and 100 muM L-NA perfusions were as follows : after 2 weeks (PF-V : 52 pA,49 pA), after 1 month(PF-V : 45 pA,ePTFE : 233 pA), after 12 months(no significant change), and after 13 months(no significant change). These results imply that the neo-intima formed on the luminal side of each vessel has ability of NO production after a short-implantation period but after long duration(about 1 year), the endothelium recognizes the physiological function of NO production to be unnecessary, thus perhaps resulting in the decrease in NO synthase activity and/or the number of NO synthase. NO production from the endothelium is directly related with the antithrombogenicity, and thus in this respect, the antithrombogenic ability of the neo-intima may be attenuated after long duration. Less