Effect of hydroxyl radical on Na(+)-K(+)-ATPase activity of the brain microsomal membranes.
Sphingomyelin liposomes and brain microsomes were oxidized by exposure to hydrogen peroxide and ferrous ion. Lipid peroxidation were measured by the formation of thiobarbituric acid- reactive substances (TBAR). Hydroxyl radical was detected using the spin- trapping technique. Incubation of sphingomyelin liposomes with H2O2-Fe2+ resulted in an increase in the formation of TBAR. Na(+)-K(+)-ATPase activity was markedly inhibited and the SH group content decreased during incubation of microsomes in the presence of H2O2-Fe2+. Sodium ferulate effectively inhibited TBAR formation, protected Na(+)-K(+)-ATPase activity and prevented the oxidative modification of SH groups. Spin-trapping experiments showed that sodium ferulate effectively scavenged the hydroxyl radicals.
Chen
J W
JW
Institute of Biophysics, Academia Sinica, Beijing, China.
Zhang
L
L
Lian
X
X
Hwang
F
F
D000818:Animals; D001923:Brain Chemistry; D003373:Coumaric Acids / Q000494:pharmacology*; D004578:Electron Spin Resonance Spectroscopy; D016166:Free Radical Scavengers; D005609:Free Radicals / Q000494:pharmacology; D006861:Hydrogen Peroxide; D006878:Hydroxides / Q000494:pharmacology*; D017665:Hydroxyl Radical; D007425:Intracellular Membranes / Q000187:drug effects / Q000378:metabolism*; D015227:Lipid Peroxidation; D008081:Liposomes; D008861:Microsomes / Q000378:metabolism; D011817:Rabbits; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013438:Sulfhydryl Compounds / Q000032:analysis
D003373:Coumaric Acids; D016166:Free Radical Scavengers; D005609:Free Radicals; D006878:Hydroxides; D008081:Liposomes; D013438:Sulfhydryl Compounds; D017665:Hydroxyl Radical; C004999:ferulic acid; D006861:Hydrogen Peroxide; D000254:Sodium-Potassium-Exchanging ATPase