OXYGEN-DERIVED FREE-RADICALS AS MEDIATORS OF VARICOSE-VEIN WALL DAMAGE

Varicose saphenous vein segments, segments of those veins with thrombo phlebitis, and segments of normal veins obtained during operation on 2 3 patients were studied to define the pattern of pro-oxidative and ant ioxidative systems in these tissues. In segments of varicose veins (VV ) the activity of superoxide dismutase (SOD) was significantly decreas ed as compared with normal veins: 7.8 +/- 2.9 vs 13.5 +/- 4.3 U/mg of protein (P < 0.05), but it was almost unchanged in the segments of VV with thrombophlebitis. The activity of glutathione reductase (GSH-R) i n all studied segments was similar and amounted to about 12.0 IU. The content of free sulfhydryl (SH) groups, the concentration of ascorbic acid, and thiobarbituric acid-reactive substances (TBA-RS) in segments of VV were significantly decreased by 40%, 48%, and 47%, respectively (P < 0.05) as compared with segments of normal veins. The values of a scorbic acid and TBA-RS in the segments of VV with thrombophlebitis we re increased by 13% and 16%, respectively, as compared with segments o f normal veins. Decreased activities of SOD and reduced levels of free SH-groups and of ascorbic acid concentration in VV may indicate impai red antioxidant mechanisms in this tissue.