title: High extracellular K+ levels stimulate acetate oxidation in brain slices from well and malnourished rats.
abstract: We investigated the effect of high (12, 20, and 50 mM) extracellular K+ concentrations ([K+]0) on [U-14C] acetate oxidation to CO2 in cerebral cortex slices of control and perinatal malnourished rats. High [K+]o increased the acetate oxidation, compared with a medium containing 2.7 mM [K+]0. By investigating the mechanisms involved in this stimulation, it was shown that (i) ouabain (1 mM) and monensin (10 microM) prevented this increase; (ii) in a medium with physiological [K+]0 (2.7 mM), the decreasing of [Na+]0 stimulated acetate oxidation. These results suggest that the stimulatory effect of [K+]0 on acetate oxidation was due to the decreasing of Na1 levels. Considering that malnutrition could alter the activity of Na+,K(+)-ATPase and/or other pertinent proteins, its effect on acetate oxidation was investigated. The malnutrition, which altered the body and cerebral weight of rats, did not modify the acetate oxidation in any protocol.
authors.affiliation: Departamento de Bioquímica, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
authors.forename: Ingrid D
authors.initials: ID
authors.lastname: Schweigert
authors.forename: Cintia
authors.initials: C
authors.lastname: Roehrig
authors.forename: Fabiane
authors.initials: F
authors.lastname: da Costa
authors.forename: Fernando
authors.initials: F
authors.lastname: Scheibel
authors.forename: Carmen J Silveria
authors.initials: CJ
authors.lastname: Gottfried
authors.forename: Liane N
authors.initials: LN
authors.lastname: Rotta
authors.forename: Carlos Alberto
authors.initials: CA
authors.lastname: Gonçalves
authors.forename: Diogo O
authors.initials: DO
authors.lastname: Souza
authors.forename: Marcos L S
authors.initials: ML
authors.lastname: Perry
mesh_terms: D000085:Acetates / Q000378:metabolism*; D000818:Animals; D001835:Body Weight; D001921:Brain / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D002540:Cerebral Cortex / Q000187:drug effects / Q000196:embryology / Q000378:metabolism; D005260:Female; D044342:Malnutrition / Q000196:embryology / Q000378:metabolism*; D008985:Monensin / Q000494:pharmacology; D010042:Ouabain / Q000494:pharmacology; D010084:Oxidation-Reduction; D011188:Potassium / Q000494:pharmacology*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D017208:Rats, Wistar; D012016:Reference Values
chemical_list: D000085:Acetates; D010042:Ouabain; D008985:Monensin; D011188:Potassium