Tricarboxylic acid-cycle metabolism in brain. Effect of fluoroacetate and fluorocitrate on the labelling of glutamate, aspartate, glutamine and gamma-aminobutyrate.
1. The effect of fluoroacetate and fluorocitrate on the compartmentation of the glutamate-glutamine system was studied in brain slices with l-[U-(14)C]glutamate, l-[U-(14)C]aspartate, [1-(14)C]acetate and gamma-amino[1-(14)C]butyrate as precursors and in homogenates of brain tissue with [1-(14)C]acetate. The effect of fluoroacetate was also studied in vivo in mouse brain with [1-(14)C]acetate as precursor. 2. Fluoroacetate and fluorocitrate inhibit the labelling of glutamine from all precursors but affect the labelling of glutamate to a much lesser extent. This effect is not due to inhibition of glutamine synthetase. It is interpreted as being due to selective inhibition of the metabolism of a small pool of glutamate that preferentially labels glutamine.
D000085:Acetates / Q000378:metabolism; D000613:Aminobutyrates / Q000378:metabolism; D000818:Animals; D001224:Aspartic Acid / Q000378:metabolism; D001921:Brain / Q000378:metabolism*; D002247:Carbon Isotopes; D002951:Citrates / Q000494:pharmacology*; D002952:Citric Acid Cycle; D005461:Fluorine / Q000494:pharmacology*; D005463:Fluoroacetates / Q000494:pharmacology*; D005971:Glutamates / Q000096:biosynthesis / Q000378:metabolism; D005973:Glutamine / Q000096:biosynthesis; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008025:Ligases / Q000037:antagonists & inhibitors; D051379:Mice
D000085:Acetates; D000613:Aminobutyrates; D002247:Carbon Isotopes; D002951:Citrates; D005463:Fluoroacetates; D005971:Glutamates; D005973:Glutamine; D005461:Fluorine; D001224:Aspartic Acid; D008025:Ligases