title: Lipoperoxidation associated with mitochondrial membrane permeabilization in the presence of Ca2+.
abstract: Lipoperoxidation was investigated as a step for membrane protein thiol oxidation of rat liver mitochondria incubated in the presence of Ca2+ and t-butylhydroperoxide, by the determination of thiobarbituric acid reactive substances. Lipoperoxidation occurred only when the incubation medium contained 125 microM t-butylhydroperoxide (t-buOOH) in the presence of Ca2+ and phosphate (Pi). No lipoperoxidation was observed when acetate replaced Pi as permeant anion, or when the oxidant was omitted, even at high Ca2+ and Pi concentrations (up to 120 microM Ca2+ and 5 mM Pi), conditions under which the mitochondria are fully permeabilized. In both cases, ADP protected efficiently against permeabilization, indicating the possible involvement of the ADP/ATP carrier in the earlier stages of the process.
authors.affiliation: Departamento de Bioquímica, Universidade Estadual de Campinas, Brasil.
authors.forename: M F
authors.initials: MF
authors.lastname: Nepomuceno
authors.forename: D V
authors.initials: DV
authors.lastname: Macedo
authors.forename: L
authors.initials: L
authors.lastname: Pereira-da-Silva
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D002463:Cell Membrane Permeability; D015227:Lipid Peroxidation; D008297:Male; D008930:Mitochondria, Liver / Q000378:metabolism*; D010758:Phosphorus / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D010758:Phosphorus; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D002118:Calcium