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Regulation of glutaminase by exogenous glutamate, ammonia and 2-oxoglutarate in synaptosomal enriched preparation from rat brain

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Abstract

Phosphate activated glutaminase in synaptosomal enriched preparation from rat brain is very sensitive to inhibition by low concentration of glutamate, ammonia and 2-oxoglutarate when added to the incubation medium at pH 7.6. By increasing the concentration of either of these compounds up to 0.5 mM a pronounced initial inhibition is followed by little or no further effect when the concentration is increased beyond this level. By lowering the pH of the reaction mixture to 7.0, the inhibition by glutamate is almost abolished and that of ammonia reduced. Glutamate inhibits mainly the N-ethylmaleimide-sensitive fraction of glutaminase which previously is suggested to be localized to the outer phase of the mitochondrial inner membrane, whereas ammonia inhibits both the N-ethylmaleimidesensitive and-insensitive fraction. Evidence has been produced to show that the inhibition by 2-oxoglutarate is caused by glutamate formation by aminotransferase reactions. Since 2-oxoglutarate is produced by the tricarboxylic acid cycle, the operation of this cycle may regulate the glutaminase reaction by controlling glutamate formation via the aminotransferase reactions.

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Abbreviations

NEM:

N-ethylmaleimide

PAG:

phosphate activated glutaminase

AOA:

aminooxyacetic acid

References

  1. Kvamme, E., andOlsen, B. E. 1979. Evidence for two species of mammalian phosphate-activated glutaminase having different regulatory properties. FEBS Lett. 107:33–36.

    Google Scholar 

  2. Kvamme, E., andOlsen, B. E. 1981. Evidence for compartmentation of synaptosomal phosphate-activated glutaminase. J. Neurochem. 36:1916–1923.

    Google Scholar 

  3. Bradford, H. F., Ward, H. K., andThomas, A. J. 1978. Glutamine—a major substrate for nerve endings. J. Neurochem. 30:1453–1459.

    Google Scholar 

  4. Reubi, J. C., Van den Berg, C. J., andCuénod, M. 1978. Glutamine as precursor for the GABA and glutamate transmitter pools. Neurosci. Lett. 10:171–174.

    Google Scholar 

  5. Tapia, R., andGonzález, R. M. 1978. Glutamine and glutamate as precursors of the releasable pool of GABA in brain cortex slices. Neurosci. Lett. 10:165–169.

    Google Scholar 

  6. Hamberger, A. C., Chiang, G. H., Nylén, E. S., Scheff, S. W., andCotman, C. W. 1979. Glutamate as a CNS transmitter. I. Evaluation of glucose and glutamine as precursors for the synthesis of preferentially released glutamate. Brain Res. 168:513–530.

    Google Scholar 

  7. Kvamme, E. 1979. Regulation of glutaminase and its possible implication for GABA metabolism, Pages 111–138,in Mandel, P., andDeFeudis, F. V., (eds.) GABA-Biochemistry and CNS Functions, Plenum Press, New York.

    Google Scholar 

  8. Tveit, B., Svenneby, G., andKvamme, E. 1970. Kinetic properties of glutaminase from pig renal cortex. Eur. J. Biochem. 14:337–344.

    Google Scholar 

  9. Svenneby, G. 1971. Activation of pig brain glutaminase. J. Neurochem. 18:2201–2208.

    Google Scholar 

  10. Bradford, H. F., andWard, H. K. 1976. On glutaminase activity in mammalian synaptosomes. Brain Res. 110:115–125.

    Google Scholar 

  11. Simpson, D. P., andAdam, W. 1975. Glutamine transport and metabolism by mitochondria from dog renal cortex. General properties and response to acidosis and alkalosis. J. Biol. Chem. 250:8148–8158.

    Google Scholar 

  12. Kvamme, E., Tveit, B., andSvenneby, G. 1970. Glutaminase from pig renal cortex. I. Purification and general properties. J. Biol. Chem. 245:1871–1877.

    Google Scholar 

  13. Whittaker, V. P., andBarker, L. A. 1972. The subcellular fractionation of brain tissue with special reference to the preparation of synaptosomes and their component organelles, Pages 1–52,in Rainer, F. (ed.) Methods of Neurochemistry, Vol. 2, Marcel Dekker, New York.

    Google Scholar 

  14. Lai, J. C. K., andClark, J. B. 1976. Preparation and properties of mitochondrial derived from synaptosomes. Biochem. J. 154:423–432.

    Google Scholar 

  15. Kvamme, E., andOlsen, B. E. 1980. Substrate mediated regulation of phosphate-activated glutaminase in nervous tissue. Brain Res. 181:228–233.

    Google Scholar 

  16. Kvamme, E., andSvenneby, G. 1975. Phosphate activated glutaminase in brain, Pages 277–290,in Marks, N., andRodnight, T. (eds.) Research Methods in Neurochemistry, Vol. 3, Plenum Press, New York.

    Google Scholar 

  17. Zamenhof, S. 1957. Preparation and assay of desoxyribonucleic acid from animal tissue, Pages 696–704,in Colowick, S. P., andKaplan, N. O. (eds.) Methods in Enzymology, Vol. 3, Academic Press, London and New York.

    Google Scholar 

  18. Weiler, C. T., Nyström, B., andHamberger, A. 1979. Glutaminase and glutamine synthetase activity in synaptosomes, bulk-isolated glia and neurons. Brain Res. 160:539–543.

    Google Scholar 

  19. Dienel, G., Ryder, E., andGreengard, O. 1977. Distribution of mitochondrial enzymes between the perikaryal and synaptic fractions of immature and adult rat brain. Biochim. Biophys. Acta 496:484–494.

    Google Scholar 

  20. Svenneby, G., Tveit, B., andKvamme, E. 1970. Glutaminase from pig renal cortex. II. Activation by inorganic and organic anions. J. Biol. Chem. 245:1878–1882.

    Google Scholar 

  21. Svenneby, G. 1970. Pig brain glutaminase: Purification and identification of different enzyme forms. J. Neurochem. 17:1591–1599.

    Google Scholar 

  22. Nimmo, G. A., andTipton, K. F. 1979. The distribution of soluble and membrane-bound forms of glutaminase in pig brain. J. Neurochem. 33:1083–1094.

    Google Scholar 

  23. Salganicoff, L., andDe Robertis, E. 1965. Subcelluar distribution of the enzyme of the glutamic acid, glutamine and γ-aminobutyric acid cycle in rat brain. J. Neurochem. 12:287–309.

    Google Scholar 

  24. Benjamin, A. M., andQuastrel, J. H. 1974. Fate of L-glutamate in the brain. J. Neurochem. 23:457–464.

    Google Scholar 

  25. Dennis, S. C., Lai, J. C. K., andClark, J. B. 1977. Comparative studies on glutamate metabolism in synaptic and non-synaptic rat brain mitochondria. Biochem. J. 164:727–736.

    Google Scholar 

  26. Kvamme, E., andLenda, K. 1981. Evidence for compartmentalization of glutamate in rat brain synaptosomes using the glutamate sensitivity of phosphate activated glutaminase as a functional test. Neurosci. Lett. 25:193–198.

    Google Scholar 

  27. Chappell, B. A. 1968. Systems used for the transport of substrates into mitochondria. Br. Med. Bull. 24:150–157.

    Google Scholar 

  28. Chapman, A. G., Meldrum, B. S., andSiesjö, B. K. 1977. Cerebral metabolic changes during prolonged epileptic seizures in rats. J. Neurochem. 28:1025–1035.

    Google Scholar 

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Kvamme, E., Lenda, K. Regulation of glutaminase by exogenous glutamate, ammonia and 2-oxoglutarate in synaptosomal enriched preparation from rat brain. Neurochem Res 7, 667–678 (1982). https://doi.org/10.1007/BF00965520

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