Effects of alpha-tocopherol on lipid peroxidation and mitochondrial reduction of tetraphenyl tetrazolium in the rat brain.
The antioxidant effect of alpha-tocopherol was assessed in a model of ischemia-reperfusion in the rat brain. In this model, permanent ischemia of the cortical branches of the middle cerebral artery was combined with bilateral occlusion of the common carotid arteries for 1 h and restoration of circulation for a period of 2 h. Lipid peroxidation and mitochondrial reduction of tetraphenyl tetrazolium (TPT) were determined in both untreated and d-alpha-tocopherol treated rats. Ferrous sulfate and ascorbic acid (FeAs) were used to induce lipid peroxidation via the formation of hydroxyl anions. Malondialdehyde (MDA) increased in the ischemia-reperfusion areas (+101%), but FeAs-induced MDA did not vary in the area of permanent ischemia. Brain tissue undergoing ischemia-reperfusion was about 50% less sensitive to the antioxidant effect of ascorbic acid. The reduction of TPT showed 52% mitochondrial damage in the area of ischemia-reperfusion, whereas mitochondrial activity in the area of permanent ischemia was 177 times lower as compared to controls. d-alpha-tocopherol caused a 40% inhibition of MDA production and 16.5% and 21.5% decrease in mitochondrial activity in the areas of ischemia-reperfusion and permanent ischemia, respectively.
Villalobos
M A
MA
Department of Anatomy, School of Medicine, University of Málaga, Spain.
De La Cruz
J P
JP
Carrasco
T
T
Smith-Agreda
J M
JM
Sánchez de la Cuesta
F
F
D000818:Animals; D001921:Brain / Q000378:metabolism*; D002545:Brain Ischemia / Q000378:metabolism*; D008054:Lipid Peroxides / Q000378:metabolism*; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008928:Mitochondria / Q000378:metabolism*; D010084:Oxidation-Reduction / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D013778:Tetrazolium Salts / Q000378:metabolism*; D014810:Vitamin E / Q000494:pharmacology*
D008054:Lipid Peroxides; D013778:Tetrazolium Salts; D014810:Vitamin E; C011314:neotetrazolium; D008315:Malondialdehyde