Catalogo Articoli (Spogli Riviste)

OPAC HELP

Titolo:
COMPARTMENTATION OF [C-14] GLUTAMATE AND [C-14] GLUTAMINE OXIDATIVE-METABOLISM IN THE RAT HIPPOCAMPUS AS DETERMINED BY MICRODIALYSIS
Autore:
ZIELKE HR; COLLINS RM; BAAB PJ; HUANG YY; ZIELKE CL; TILDON JT;
Indirizzi:
UNIV MARYLAND,DEPT PEDIAT,10-035 BRB,655 W BALTIMORE ST BALTIMORE MD 21201
Titolo Testata:
Journal of neurochemistry
fascicolo: 3, volume: 71, anno: 1998,
pagine: 1315 - 1320
SICI:
0022-3042(1998)71:3<1315:CO[GA[>2.0.ZU;2-5
Fonte:
ISI
Lingua:
ENG
Soggetto:
IN-VIVO OXIDATION; EXOGENOUS GLUTAMATE; PRIMARY CULTURES; HUMAN BRAIN; ASTROCYTES; ADULT; FATE; NEURONS;
Keywords:
BRAIN ENERGY METABOLISM; OXIDATION; MICRODIALYSIS; GLUTAMATE; GLUTAMINE;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Science Citation Index Expanded
Science Citation Index Expanded
Citazioni:
28
Recensione:
Indirizzi per estratti:
Citazione:
H.R. Zielke et al., "COMPARTMENTATION OF [C-14] GLUTAMATE AND [C-14] GLUTAMINE OXIDATIVE-METABOLISM IN THE RAT HIPPOCAMPUS AS DETERMINED BY MICRODIALYSIS", Journal of neurochemistry, 71(3), 1998, pp. 1315-1320

Abstract

Metabolic compartmentation of amino acid metabolism in brain is exemplified by the differential synthesis of glutamate and glutamine from the identical precursor and by the localization of the enzyme glutaminesynthetase in glial cells. In the current study, we determined if theoxidative metabolism of glutamate and glutamine was also compartmentalized. The relative oxidation rates of glutamate and glutamine in the hippocampus of free-moving rats was determined by using microdialysis both to infuse the radioactive substrate and to collect (CO2)-C-14 generated during their oxidation. At the end of the oxidation experiment,the radioactive substrate was replaced by artificial CSF, 2 min-fractions were collected, and the specific activities of glutamate and glutamine were determined. Extrapolation of the specific activity back to the time that artificial CSF replaced C-14-amino acids in the microdialysis probe yielded an approximation of the interstitial specific activity during the oxidation. The extrapolated interstitial specific activities for [C-14]glutamate and [C-14] glutamine were 59 +/- 18 and 2.1+/- 0.5 dpm/pmol, respectively. The initial infused specific activities for [U-C-14] glutamate and [U-C-14] glutamine were 408 +/- 8 and 387 +/- 1 dpm/pmol, respectively. The dilution of glutamine was greater than that of glutamate, consistent with the difference in concentrations of these amino acids in the interstitial space. Based on the extrapolated interstitial specific activities,the rate of glutamine oxidation exceeds that of glutamate oxidation by a factor of 5.3. These data indicate compartmentation of either uptake and/or oxidative metabolism of these two amino acids. The presence of [C-14]glutamine in the interstitial space when [C-14]glutamate was perfused into the brain provided further evidence for the glutamate/glutamine cycle in brain.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 26/01/20 alle ore 00:45:02