Fig. 1

Schematic diagram illustrating the relation between the metabolism of valproic acid and those of amino acids associated with the urea cycle. The symbols 〔 ↑, ↓〕, − and ± indicate increase, decrease, stable, and either increase or decrease in the concentrations of the respective amino acids or substances. Abbreviations: CPS1: carbamoyl-phosphate synthase 1, NAG: N-acetyl glutamic acid