title: Inhibition of Na(+),K(+)-ATPase activity in hippocampus of rats subjected to acute administration of homocysteine is prevented by vitamins E and C treatment.
abstract: In the present study we evaluated the effect of acute homocysteine (Hcy) administration on Na(+),K(+)-ATPase activity, as well as on some parameters of oxidative stress such as total radical-trapping antioxidant potential (TRAP) and on activities of antioxidant enzymes catalase (CAT), superoxide dismutase and glutathione peroxidase in rat hippocampus. Results showed that Hcy significantly decreased TRAP, Na(+),K(+)-ATPase and CAT activities, without affecting the activities of superoxide dismutase and glutathione peroxidase. We also verified the effect of chronic pretreatment with vitamins E and C on the reduction of TRAP, Na(+),K(+)-ATPase and CAT activities caused by Hcy. Vitamins E and C per se did not alter these parameters, but prevented the reduction of TRAP, Na(+),K(+)-ATPase and CAT activities caused by Hcy. Our results indicate that oxidative stress is probably involved in the pathogenesis of homocystinuria and that reduction of Na(+),K(+)-ATPase activity may be related to the neuronal dysfunction found in homocystinuric patients.
authors.affiliation: Departamento de Bioquímica, ICBS, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil. wyse@ufrgs.br
authors.forename: Angela T S
authors.initials: AT
authors.lastname: Wyse
authors.forename: Alexandra I
authors.initials: AI
authors.lastname: Zugno
authors.forename: Emilio L
authors.initials: EL
authors.lastname: Streck
authors.forename: Cristiane
authors.initials: C
authors.lastname: Matté
authors.forename: Thiago
authors.initials: T
authors.lastname: Calcagnotto
authors.forename: Clovis M D
authors.initials: CM
authors.lastname: Wannmacher
authors.forename: Moacir
authors.initials: M
authors.lastname: Wajner
mesh_terms: D000818:Animals; D001205:Ascorbic Acid / Q000494:pharmacology*; D002374:Catalase / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D006624:Hippocampus / Q000187:drug effects* / Q000201:enzymology; D006710:Homocysteine / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors*; D013482:Superoxide Dismutase / Q000378:metabolism; D014810:Vitamin E / Q000494:pharmacology*
chemical_list: D006710:Homocysteine; D014810:Vitamin E; D002374:Catalase; D005979:Glutathione Peroxidase; D013482:Superoxide Dismutase; D000254:Sodium-Potassium-Exchanging ATPase; D001205:Ascorbic Acid