Brain Na+,K(+)-ATPase inhibition induced by arginine administration is prevented by vitamins E and C.
Hyperargininemia is a metabolic disorder caused by deficiency of arginase activity resulting in tissue accumulation of arginine and neurological dysfunction. We have previously demonstrated that arginine induces oxidative stress and decreases Na+,K(+)-ATPase in rat midbrain. In the present study we investigated the action of vitamins E and C on the inhibition of Na+,K(+)-ATPase provoked by arginine in the midbrain of 60-day-old rats. Animals were pretreated for 1 week with daily IP administration of saline (control) or vitamins E (40 mg/kg) and C (100 mg/kg). Twelve h after the last injection, animals received one injection of arginine (0.8 micromol/g of body weight) or saline. Chemiluminescence was significantly increased, whereas total antioxidant capacity and Na+,K(+)-ATPase activity were significantly decreased. Furthermore, treatment with vitamins E and C prevented these effects. If these effects also occur in the human condition, it is possible that antioxidant administration might slow the progression of neurodegeneration in this disorder.
Bavaresco
Caren S
CS
Departamento de Bioquímica, ICBS, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003, Porto Alegre, RS, Brazil.
Calcagnotto
Thiago
T
Tagliari
Bárbara
B
Delwing
Daniela
D
Lamers
Marcelo L
ML
Wannmacher
Clóvis M D
CM
Wajner
Moacir
M
Wyse
Angela T S
AT
D000818:Animals; D001120:Arginine / Q000494:pharmacology*; D001205:Ascorbic Acid / Q000494:pharmacology*; D020162:Hyperargininemia; D008297:Male; D008636:Mesencephalon / Q000201:enzymology*; D051381:Rats; D017208:Rats, Wistar; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D014810:Vitamin E / Q000494:pharmacology*
D014810:Vitamin E; D001120:Arginine; D000254:Sodium-Potassium-Exchanging ATPase; D001205:Ascorbic Acid