RESUMO
<p><b>OBJECTIVE</b>To explore the relationship between plasma redox status and atherosclerosis.</p><p><b>METHODS</b>IVUS was performed in common carotid in the neck of 167 patients with heart diseases. Patients were divided into three groups: plaque-forming group (A, n = 79), intima-thickening group (B, n = 52) and control group (C, n = 36). Plasma glutathione (reduced form GSH and oxidized form GSSG), nicotinamide adenine dinucleotide phosphate (reduced form NADPH and oxidized form NADP(+)), oxidized low density lipoprotein (ox-LDL) and malondialdehyde (MDA) were measured in all patients. The GSH/GSSG and NADPH/NADP(+) redox potential were calculated according to Nernst equation, and correlation analysis performed.</p><p><b>RESULTS</b>GSH and GSH/GSSG gradually reduced and GSH/GSSG redox potential gradually increased in proportion to the thickening of artery intima (from Group C to Group A, P < 0.05). Similar but milder results were shown for NADPH and NADPH/NADP(+) redox status. The products of oxidative stress ox-LDL and MDA also increased significantly (P < 0.05) in proportion to the thickening of artery intima. GSH/GSSG redox potential is positively correlated to ox-LDL (P < 0.05). The redox status shifted to oxidizing direction in proportion to the intima thickness.</p><p><b>CONCLUSION</b>The imbalance of plasma redox status deviating to oxidation might be implicated in oxidized injury of lipid, intima thickening and atherosclerosis progress.</p>