[Kinetics of lipid peroxidation induced by Fe2+ ions in a suspension of mitochondrial and nuclear membranes].

Kinetics of TBARS accumulation, Fe2+ oxidation, and chemiluminescence were measured in nuclear and mitochondrial membrane suspensions during Fe(2+)-induced lipid peroxidation development. Above certain critical Fe2+ concentrations ([Fe2+].) the latent period (t) of lipid peroxidation development were observed. By using the dependence of t on [Fe2+] the [Fe2+]. values were measured in nuclear and mitochondrial membrane suspensions. At the same concentrations of nuclear and mitochondrial membranes (1 mg/ml) the [Fe2+] value changed from 10 to 30 mu kM. In the case of nuclear membrane suspension the [Fe2+] value changed from 20 to 30 mu kM with the change of membrane concentrations from 0.5 to 1.5 mg/ml. For mitochondrial membrane suspension [Fe2+]. value increased from 10 to 40 mu kM with increasing membrane concentrations from 1 to 4 mg/ml. Apparently, [Fe2+]. value is the main parameter determining the kinetics of Fe(2+)-induced lipid peroxidation in native membrane preparations; the [Fe2+]. value in different membrane systems, in turn, is dependent on the ability of the membrane to bind Fe2+ ions.