Vitamin C prevents radiation-induced endothelium-dependent vasomotor dysfunction and de-endothelialization by inhibiting oxidative damage in the rat.

摘要: 1. The present study was undertaken to determine whether endothelial function or morphology altered in aortic rings of rats after irradiation, investigate the mechanism radiation effects on endothelium and examine effect vitamin C treatment against radiation-induced damage endothelium. 2. Female Sprague-Dawley were randomized into four groups (control, radiation, + C, NG-nitro-L-arginine methyl ester (L-NAME); n = 10 for each group 7 control group) irradiated with Gy 137Cs as a source. Segments thoracic aorta obtained isometric tension, levels 8-hydroxydeoxyguanosine (OH-dG) immunohistochemical staining measured. 3. Irradiation significantly impaired acetylcholine-induced vasodilation segments, an that could be prevented by pretreatment (500 mg/kg per day). This beneficial abolished addition L-NAME (100 microg/kg day), inhibitor nitric oxide (NO) synthesis. increased level OH-dG (1.02 +/- 0.27 vs 2.61 0.78 OH-dG/105 deoxyguanosine (dG) tissues, respectively; P < 0.01), increase (1.59 0.23 dG; 0.01). caused significant de-endothelialization (von Willebrand factor (vWF) 93 100% 0.05) this (vWF 98 3%; 0.05). 4. Radiation NO production through oxidative injury, resulting selective impairment endothelial-dependent partly anti-oxidant mechanisms.