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. 1983 Oct 15;216(1):233–236. doi: 10.1042/bj2160233

Inhibition of ureagenesis by valproate in rat hepatocytes. Role of N-acetylglutamate and acetyl-CoA.

F X Coude, G Grimber, P Parvy, D Rabier, F Petit
PMCID: PMC1152491  PMID: 6418145

Abstract

Valproate (0.5-5 mM) strongly inhibited urea synthesis in isolated rat hepatocytes incubated with 10 mM-alanine and 3 mM-ornithine. Valproate at the same concentrations markedly decreased concentrations of N-acetylglutamate, an essential activator of carbamoyl-phosphate synthetase I (EC 6.3.4.16), in parallel with the inhibition of urea synthesis by valproate. This compound also lowered the cellular concentration of acetyl-CoA, a substrate of N-acetylglutamate synthase (EC 2.3.1.1); glutamate, aspartate and citrulline were similarly decreased. Valproate in a dose up to 2 mM did not significantly affect the cellular concentration of ATP and had no direct effect on N-acetylglutamate synthesis, carbamoyl-phosphate synthetase I and ornithine transcarbamoylase (EC 2.1.3.3) activities.

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Selected References

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

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