A novel biochemically salvageable animal model of hyperammonemia devoid of N-acetylglutamate synthase

► A salvageable mouse model of a complete urea cycle disorder has been developed. ► Homozygous NAGS knockout mouse is rescued by N-carbamylglutamate and l-citrulline. ► On rescue chemicals, the homozygous mouse reaches adulthood and reproduces. ► Off rescue, the mouse dies within 24-48 h from hyperammonemia. ► The mouse model recapitulates a severe proximal urea cycle disorder.