[The effect of uric acid, creatine phosphate and carnitine on lipid peroxidation in cerebral cortex and myocardium homogenates].

Background: Uric acid as the product of purine nucleotide degradation is an integrate component of blood plasma. This metabolite is considered to be one of the important naturally occurring antioxidants building up the antioxidation system of the organism. Creatine phosphate and carnitine are important substances participating in energy metabolism of the cells. Energy production is closely related to the level of reduction systems and thus also to the antiradical ability of the cell. By this mechanism could creatine phosphate and carnitine improve the antioxidative capacity of the cell.

Methods: In homogenates of rat brain cortex and myocardium was the production of oxygen radicals stimulated by mixture of Fe2+ ions and ascorbate. Oxygen radicals may induce lipid peroxidation by the means of the reaction with lipid structures. We tried to inhibit the process of lipid peroxidation by addition of uric acid, creatine phosphate and carnitine into the incubation medium. Intensity of lipoperoxidation was measured by detection of substances giving positive reaction with thiobarbituric acid (TBA) in homogenates of brain cortex and myocardium.

Results: Uric acid in concentrations of 1 and 0.5 mmol.l-1 markedly inhibits the production of compounds reacting with TBA. This effect was not found in 0.05 mmol.l-1 concentration. Creatine phosphate and carnitine in 1 mmol.l-1 concentrations also decreased the value of lipid peroxides in homogenates of brain cortex, but their effect was lower than the effect of uric acid. This effect was not seen in myocardium homogenates.