Liver arginase(Arginase-1) belongs to the arginase family. Hepatic arginase 1 is closely associated with alternative macrophage activation(PMID:12098359) and Arg1 has been shown to protectmotor neurons from trophic factor deprivation and allow sensory neurons to overcome neurite outgrowth inhibition by myelin proteins(PMID: 20071539).It can exsit as a homotrimer(PMID:16141327) and it has 3 isoforms produced by alternative splicing.Defects in ARG1 are the cause of argininemia (ARGIN).