Reduction of energy metabolism in rat hippocampus by arginine administration.
Hyperargininemia is an inherited metabolic disease biochemically characterized by tissue accumulation of arginine. Mental retardation and other neurological features are common symptoms in hyperargininemic patients. Considering that the underlying mechanisms of brain damage in this disease are poorly established, in this work we investigated the effect of arginine administration to adult Wistar rats on some parameters of energy metabolism (CO(2) production, glucose uptake, lactate release and the activities of succinate dehydrogenase, complexes II and IV of the respiratory chain) in rat hippocampus. The action of L-NAME, an inhibitor of oxide nitric oxide synthase, on the effects produced by arginine was also tested. Sixty-day-old rats were treated with a single intraperitoneal injection of saline (group I, control), arginine (0.8 g/kg) (group II) or arginine (0.8 g/kg) plus L-NAME (2 mg/kg) (group III) and were killed 1 h later. Results showed that arginine administration significantly increased lactate release and diminished CO(2) production, glucose uptake, succinate dehydrogenase and complex II activities. In contrast, complex IV (cytochrome c oxidase) activity was not changed by this amino acid. Furthermore, simultaneous injection of L-NAME prevented some of these effects, except CO(2) production and lactate release. The present data indicate that in vivo arginine administration impairs some parameters of energy metabolism in hippocampus of rats probably through NO formation.
Delwing
Débora
D
Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Rua Ramiro Barcelos, 2600-Anexo, CEP 90035-003, RS, Porto Alegre, Brazil.
Tagliari
Bárbara
B
Streck
Emílio Luiz
EL
Wannamacher
Clovis Milton Duval
CM
Wajner
Moacir
M
Wyse
Angela Terezinha de Souza
AT
D000818:Animals; D001120:Arginine / Q000494:pharmacology*; D002245:Carbon Dioxide / Q000378:metabolism; D003864:Depression, Chemical; D004579:Electron Transport / Q000187:drug effects; D003576:Electron Transport Complex IV / Q000378:metabolism; D004734:Energy Metabolism / Q000187:drug effects*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005947:Glucose / Q000378:metabolism; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism*; D007202:Indicators and Reagents; D019344:Lactic Acid / Q000378:metabolism; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009569:Nitric Oxide / Q000502:physiology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D052248:Nitric Oxide Synthase Type I; D051381:Rats; D017208:Rats, Wistar; D013385:Succinate Dehydrogenase / Q000378:metabolism
D004791:Enzyme Inhibitors; D007202:Indicators and Reagents; D009419:Nerve Tissue Proteins; D002245:Carbon Dioxide; D009569:Nitric Oxide; D019344:Lactic Acid; D001120:Arginine; D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I; C496322:Nos1 protein, rat; D013385:Succinate Dehydrogenase; D003576:Electron Transport Complex IV; D005947:Glucose; D019331:NG-Nitroarginine Methyl Ester