– Arginase-2 (ARG2) is a member of the arginase family. Arginase is a manganese-containing enzyme which catalyzes the hydrolysis of arginine to ornithine and urea. ARG2 is highly expressed in kidney and prostate, not founded in the liver, heart and pancreas. ARG2 has been implicated in the regulation of the arginine/ornithine concentrations in the cell. ARG2 may take part in the regulation of extra-urea cycle arginine metabolism and in down-regulation of nitric oxide synthesis. The extrahepatic arginase functions to regulate L-arginine bioavailability to NO synthase.