Oxidative and antioxidant changes during formation of unstable atherosclerotic plaque.

Oxidative and antioxidant parameters (content of LPO products and oxidized proteins, initial level of paraoxonase, content of alpha-tocopherol, retinol, and beta-carotene) were studied at different stages of atherosclerotic foci development in coronary arteries: intact intima, lipid spot, stable young plaque, unstable plaque, stable plaque with fibrosis/ calcinosis, and in various types of unstable plaques. The most typical sign of unstable plaques is high level of LPO products and low retinol content.