Effect Of Apocynin On Oxidative Stress Injury To Vascular Endothelial Cells Of Rabbit Vein In Vitro

Objective: To investigate the protection and mechanism of the NADPH oxidase inhibitor Apocynin on oxidative stress injury to rabbit jugular vein in vitro.Methods: 18 New Zealand rabbits were randomly divided into experimental and control group,the rabbits of experimental group were gavaged with NADPH oxidase inhibitor Apocynin 15mg which was diluted with water to 10ml, the control group were gavaged 10ml water as a placebo.Two weeks after administration the bilateral jugular veins of rabbits were harvested and preserved at 37℃for 90 minutes,then the samples were fixed. NADPH oxidase subunit p47phox expression was measured by immunofluorescence and Western blotting analysis; MDA was detected by TBA, the ultrastructural injury of endothelial cells was observed under electron microscope.Results: By immunofluorescence stain, light green fluorescence was observed in the endothelial cells in the experimental group, and bright green fluorescence was observed in the control group.Detected by western blotting, the expression of p47phox protein (124.23±6.94) in the exprimental group was significantly lower than that (137.17±15.91) in the control group(p﹤0.05), suggesting that the expression of NADPH oxidase in the experimental group was suppressed; MDA (1.98±0.35) in the exprimental group was significantly lower than that (2.13±0.16) in the control group(p﹤0.001), suggesting that the oxidative stress injury was less severe. There were ultrastructural injuries at different degrees observed in the endothelial cells under electron microscope in both groups,but the injuries in the experimental group were less severe than those in the control group, and injuries were closely related to wether Apocynin was applied or not.Conclusion:Apocynin suppressed the expression of NADPH oxidase p47phox in the vascular endothelial cells with oxidative stress injury in vitro and protected the vein grafts more effectively. The mechanism might be that Apocynin inhibit the NADPH oxidase, decreased the release of reactive oxygen species and attenuated oxidative stress injury.