Reaction between lipid hydroperoxide and hemoglobin studied by a spectrophotometric and a spin trapping method.

Abstract

The reaction between lipid hydroperoxide and hemoglobin (Hb) under aerobic condition was studied kinetically by a spectrophotometric and a spin trapping method. The reaction did not follow simple first order or second order kinetics, possibly because Hb was also decomposed during the decomposition of lipid hydroperoxide. A spin trap reagent decreased the rate of the reaction. Some free radicals were trapped by the spin trap reagent and their structures were found from ESR spectra of spin adducts. These results were explained by a free-radical chain reaction mechanism initiated by lipid hydroperoxide and Hb.