Carboxypeptidase activity in human urine from healthy subjects and renal disease patients

• Published in: Clinica chimica acta Vol. 188; no. 3; pp. 233 - 241
• Main Authors: Hamai, Keiko, Ikeda, Ryuzoh, Sumi, Hiroyuki, Mihara, Hisashi
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier B.V 01.05.1990; Elsevier
• Subjects: Analytical, structural and metabolic biochemistry; Biological and medical sciences; Cadmium - pharmacology; Carboxypeptidase; Carboxypeptidases - antagonists & inhibitors; Carboxypeptidases - urine; Cobalt - pharmacology; Colorimetric assay; Colorimetry - methods; Copper - pharmacology; Enzyme Stability; Enzymes and enzyme inhibitors; Female; Fundamental and applied biological sciences. Psychology; Humans; Hydrogen-Ion Concentration; Hydrolases; Kidney Diseases - enzymology; Male; Mercury - pharmacology; Nickel - pharmacology; Renal disease; Serum Albumin, Bovine - pharmacology; Substrate Specificity; Urine; Urine; Colorimetric assay; Renal disease; Carboxypeptidase; Human; Biological fluid; Urinary system disease; Enzyme; Clinical biology; Biological marker; Colorimetry; Kidney; Quantitative analysis; Ultraviolet visible spectrometry
• ISSN: 0009-8981; 1873-3492
• DOI: 10.1016/0009-8981(90)90205-7

We have attempted to estimate the Carboxypeptidase activity in unconcentrated human urine by means of a colorimetric method in which Bz-Gly-Lys is employed as a substrate. Upon addition of both 1.6 mmol/l CoCl 2 and 0.18 g/l bovine serum albumin to the assay solution at pH 5.6, the Carboxypeptidase activity in human urine can be evaluated. Using our method, the daily excretion of Carboxypeptidase in both healthy subjects and patients with renal diseases has been examined. The level is increased in patients with nephrotic glomerulonephritis (24.9 ± 14.9 (SD) U/day; n = 8) and patients with nephritic glomerulonephritis (11.4 ± 7.55 (SD) U/day; n = 14) as compared to that in healthy subjects (5.10 ± 1.88 (SD) U/day; n = 18). However, it is decreased in patients with chronic renal failure (2.70 ± 2.13 (SD) U/day; n = 12).