Abstract
The study was performed on 50 urine specimens of patients with chronic renal failure ,in addition to the 92 healthy specimens as a control group. The results of the study revealed that Alanine aminopeptidase (AAP) activity of chronic renal failure patients urine shows a highly significant increase (p<0.0001) compared to healthy subjects. Alanine aminopeptidase was purified from urine patients with chronic renal failure and healthy subjects by gel filtration using sephadex G-50, and two isoenzyms of (AAP) I, II were separated from patients urine using anion exchanger (DEAE-sephdexA-50).