Lipid peroxidation and its inhibition by tinoridine, II. Ascorbic acid-induced lipid peroxidation of rat liver mitochondria.
Incubation of rat liver mitochondrial suspension with ascorbic acid and Fe2+ resulted in the formation of malondialdehyde and a decrease in the turbidity of the suspension. The maximum amount of malondialdehyde formed during the peroxidation reaction was estimated to be 1 mol per approximately 6 mol of mitochondrial phospholipids. Tinoridine and alpha-tocopherol at the concentration of 5 micron and 1 mM, respectively, completely inhibited the peroxidative disintegration of mitochondria. From the relationship between the concentration of tinoridine and the amount of malondialdehyde formed, it was demonstrated that 1 mol of tinoridine prevents the formation of about 6 mol of malondialdehyde. These findings suggest that there is a limit in the chain reaction of the lipid peroxidation of mitochondria and that the limit is the membrane sphere which is capable of releasing 6 molecules of malondialdehyde and contains about 36 molecules of the constitutive phospholipids.
D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology*; D005296:Ferrous Compounds / Q000494:pharmacology; D050356:Lipid Metabolism; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008930:Mitochondria, Liver / Q000378:metabolism*; D010545:Peroxides / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology*; D051381:Rats; D014810:Vitamin E / Q000494:pharmacology
D005296:Ferrous Compounds; D010545:Peroxides; D011725:Pyridines; D014810:Vitamin E; D008315:Malondialdehyde; D001205:Ascorbic Acid