13C-n.m.r. study of citrate metabolism in rabbit renal proximal-tubule cells.
The metabolism of a 13C-labelled substrate, [3-13C]citrate, was monitored in rabbit renal proximal-tubule cells by 13C n.m.r. The relative enrichments of label in glutamate, glutamine and alpha beta-glucose allowed a calculation of the rate of the glutamate dehydrogenase flux relative to the flux via phosphoenolpyruvate carboxykinase. A ratio of 1.2 +/- 0.05 was found. Under steady-state conditions of active gluconeogenesis, the ratio of flux through pyruvate kinase to the gluconeogenic rate was 0.97 +/- 0.03.
Jans
A W
AW
Max-Planck-Institut für Systemphysiologie, Dortmund, Federal Republic of Germany.
Winkel
C
C
Buitenhuis
L
L
Lugtenburg
J
J
D000818:Animals; D002951:Citrates / Q000378:metabolism*; D019343:Citric Acid; D002952:Citric Acid Cycle; D005971:Glutamates / Q000378:metabolism; D018698:Glutamic Acid; D007687:Kidney Tubules, Proximal / Q000166:cytology / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D011817:Rabbits
D002951:Citrates; D005971:Glutamates; D019343:Citric Acid; D018698:Glutamic Acid