title: Optimized assay for serum angiotensin-converting enzyme activity.
abstract: This optimized two-point kinetic assay for serum angiotensin-converting enzyme is based on the colorimetric determination of hippurate with cyanuric chloride/dioxan reagent. The hippurate is released from hippuryl-L-histidyl-L-leucine by angiotensin-converting enzyme in the presence of chloride ion. CVs for the method (within-run and between-run) ranged from 2.1 to 3.2%. Linearity extends up to 200 U/L. Results are unaffected by lipemia and icterus. Hemoglobin in concentrations greater than 1.5 g/L causes a slight negative interference. Reference intervals for men and women are 22-82 U/L and 25-69 U/L, respectively.
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002021:Buffers; D055598:Chemical Phenomena; D002621:Chemistry; D002648:Child; D002675:Child, Preschool; D003124:Colorimetry / Q000379:methods; D005260:Female; D006626:Hippurates / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008168:Lung / Q000201:enzymology; D008297:Male; D008875:Middle Aged; D009842:Oligopeptides / Q000378:metabolism; D007703:Peptidyl-Dipeptidase A / Q000097:blood*; D010710:Phosphates; D012016:Reference Values; D014227:Triazines
chemical_list: D002021:Buffers; D006626:Hippurates; D009842:Oligopeptides; D010710:Phosphates; D014227:Triazines; C010980:hippuryl-histidyl-leucine; C019309:cyanuric chloride; D007703:Peptidyl-Dipeptidase A