Skip to main content
Biochemical Journal logoLink to Biochemical Journal
. 1966 Oct;101(1):242–249. doi: 10.1042/bj1010242

The fate of isotopic carbon in kidney cortex synthesizing glucose from lactate

H A Krebs 1, R Hems 1, M J Weidemann 1, R N Speake 1
PMCID: PMC1270089  PMID: 5971786

Abstract

1. When slices of kidney cortex are incubated with lactate and acetoacetate, lactate is almost quantitatively converted into glucose whereas acetoacetate provides a major part of the fuel of respiration. 2. In apparent contrast with these findings a large fraction of 14C-labelled acetoacetate appears in glucose and a large fraction of 14C-labelled lactate appears in the carbon dioxide. 3. The findings can be explained by: (a) the participation of oxaloacetate as an intermediate of both gluconeogenesis and respiration; (b) the fact that the carbon dioxide formed in the course of one turn of the tricarboxylic acid cycle is exclusively derived from oxaloacetate. 4. As a result there is a `crossing over' of the carbon of the substrate of respiration to the pathway of gluconeogenesis and of the carbon of the glucogenic precursors to the pathway of respiration. 5. In the given situation the fate of the label does not allow predictions to be made about the net fate of the labelled metabolites. 6. The implications of the findings on the interpretation of isotopic data are discussed.

Full text

PDF
242

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. ALLWEIS C. L., GAINER H., CHAIKOFF I. L. Method for kinetic study of in vitro conversion of a C14-labeled substrate to CO2. J Appl Physiol. 1960 Sep;15:949–952. doi: 10.1152/jappl.1960.15.5.949. [DOI] [PubMed] [Google Scholar]
  2. ANNISON E. F., LINDSAY D. B. Acetate utilization in sheep. Biochem J. 1961 Apr;78:777–785. doi: 10.1042/bj0780777. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Ashby M. M., Heath D. F., Stoner H. B. A quantitative study of carbohydrate metabolism in the normal and injured rat. J Physiol. 1965 Jul;179(2):193–237. doi: 10.1113/jphysiol.1965.sp007658. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. BRYANT C., SMITH M. J., HINES W. J. Effects of salicylate and gamma-resorcylate on the metabolism of radioactive succinate and fumarate by rat-liver mitochondria and on dehydrogenase enzymes. Biochem J. 1963 Mar;86:391–396. doi: 10.1042/bj0860391. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. CROWLEY G. J., MOSES V., ULLRICH J. A VERSATILE SOLVENT TO REPLACE PHENOL FOR THE PAPER CHROMATOGRAPHY OF RADIOACTIVE INTERMEDIARY METABOLITES. J Chromatogr. 1963 Oct;12:219–228. doi: 10.1016/s0021-9673(01)83673-6. [DOI] [PubMed] [Google Scholar]
  6. GAITONDE M. K., DAHL D. R., ELLIOTT K. A. ENTRY OF GLUCOSE CARBON INTO AMINO ACIDS OF RAT BRAIN AND LIVER IN VIVO AFTER INJECTION OF UNIFORMLY 14-C-LABELLED GLUCOSE. Biochem J. 1965 Feb;94:345–352. doi: 10.1042/bj0940345. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Gevers W., Krebs H. A. The effects of adenine nucleotides on carbohydrate metabolism in pigeon-liver homogenates. Biochem J. 1966 Mar;98(3):720–735. doi: 10.1042/bj0980720. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. HASLAM R. J., KREBS H. A. THE METABOLISM OF GLUTAMATE IN HOMOGENATES AND SLICES OF BRAIN CORTEX. Biochem J. 1963 Sep;88:566–578. doi: 10.1042/bj0880566. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. KREBS H. A., BENNETT D. A., DE GASQUET P., GASQUET P., GASCOYNE T., YOSHIDA T. Renal gluconeogenesis. The effect of diet on the gluconeogenic capacity of rat-kidney-cortex slices. Biochem J. 1963 Jan;86:22–27. doi: 10.1042/bj0860022. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. KREBS H. A., SPEAKE R. N., HEMS R. ACCELERATION OF RENAL GLUCONEOGENESIS BY KETONE BODIES AND FATTY ACIDS. Biochem J. 1965 Mar;94:712–720. doi: 10.1042/bj0940712. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. KREBS H. THE CROONIAN LECTURE, 1963. GLUCONEOGENESIS. Proc R Soc Lond B Biol Sci. 1964 Mar 17;159:545–564. doi: 10.1098/rspb.1964.0019. [DOI] [PubMed] [Google Scholar]
  12. Krebs H. A., De Gasquet P. Inhibition of gluconeogenesis by alpha-oxo acids. Biochem J. 1964 Jan;90(1):149–154. doi: 10.1042/bj0900149. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Krebs H. A., Eggleston L. V. Metabolism of acetoacetate in animal tissues. 1. Biochem J. 1945;39(5):408–419. [PMC free article] [PubMed] [Google Scholar]
  14. READING H. W. METABOLISM OF ENDOGENOUS SUBSTRATE IN THE RETINA. Nature. 1963 Aug 24;199:817–818. doi: 10.1038/199817a0. [DOI] [PubMed] [Google Scholar]
  15. SEARLE G. L., CHAIKOFF I. L. Inhibitory action of hyperglycemia on delivery of glucose to the blood stream by liver of the normal dog. Am J Physiol. 1952 Aug;170(2):456–460. doi: 10.1152/ajplegacy.1952.170.2.456. [DOI] [PubMed] [Google Scholar]
  16. SEARLE G. L., STRISOWER E. H., CHAIKOFF I. L. Glucose pool and glucose space in the normal and diabetic dog. Am J Physiol. 1954 Feb;176(2):190–194. doi: 10.1152/ajplegacy.1954.176.2.190. [DOI] [PubMed] [Google Scholar]
  17. VRBA R., GAITONDE M. K., RICHTER D. The conversion of glucose carbon into protein in the brain and other organs of the rat. J Neurochem. 1962 Sep-Oct;9:465–475. doi: 10.1111/j.1471-4159.1962.tb04199.x. [DOI] [PubMed] [Google Scholar]
  18. VRBA R. UTILIZATION OF GLUCOSE CARBON IN VIVO IN THE MOUSE. Nature. 1964 Apr 18;202:247–249. doi: 10.1038/202247a0. [DOI] [PubMed] [Google Scholar]
  19. WEINMAN E. O., STRISOWER E. H., CHAIKOFF I. L. Conversion of fatty acids to carbohydrate; application of isotopes to this problem and role of the Krebs cycle as a synthetic pathway. Physiol Rev. 1957 Apr;37(2):252–272. doi: 10.1152/physrev.1957.37.2.252. [DOI] [PubMed] [Google Scholar]
  20. WILLIAMSON D. H., MELLANBY J., KREBS H. A. Enzymic determination of D(-)-beta-hydroxybutyric acid and acetoacetic acid in blood. Biochem J. 1962 Jan;82:90–96. doi: 10.1042/bj0820090. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. WILLIAMSON J. R., KREBS H. A. Acetoacetate as fuel of respiration in the perfused rat heart. Biochem J. 1961 Sep;80:540–547. doi: 10.1042/bj0800540. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Biochemical Journal are provided here courtesy of The Biochemical Society

RESOURCES