I tried to purify of bovine β
2-microglobulin (β
2-m) and produced assay methods of β
2-m and albumin (Alb). The clinical dynamisms of these urinary proteins compared with a various kinds of renal function test, and it was examined diagnostic significance. Bovine β
2-m was purified from colostrum and. the urine sample of cows intravenously injected potassium dichromate by two phases chromatography (negative ion exchange and gel chromatography). The molecular weight of bovine β
2-m was 11.9-11.8 kDa calculated by SDS-PAGE, and bovine β
2-m includes four isoform, its isoelectric points were pI 7.1, 7.0, 7.5 and 7.8. In addition, bovine β
2-m consist of 98 amino acids and the 17th, 72nd and 76th amino acid were Asp, Asn and Gln, respectively. The assay of bovine β
2-m was applied for sandwich enzyme linked immunosorbent assay (ELISA) that used of avidin-biotin peroxidase complex, and the assay of bovine urinary Alb concentration was applied single radial immunodiffusion (SRID). The normal reference ranges of bovine β
2-m assay were followed. Serum concentration (Sb2), urinary concentration (Ub2), excretion rate into urine (Eb2), clearance (Cb2), creatinine index (Ib2) of β
2-m were 3.6±1.35mg/ml (Mean±SD), 33.0±24.9ng /ml, 514.0±435.3ng/min, 0.27±0.25ml/min/kg and 0.118±0.118ng/mg, respectively. The normal reference ranges of bovine Alb assay were followed. Urinary concentration (UAlb), excretion rate into urine (EAlb), clearance (CAlb), creatinine index (IAlb) of Alb were 70±64mg/ml, 806.1±374.5mg/min, 0.05±0.02m1/min/kg and 0.24±0.30mg/ mg, respectively. In order to examine significance of a diagnosis of β
2-m and Alb, 11 cows with an urinary organ disease and 3 cows experimentally distracted renal function assayed urinary β
2-m and Alb, tested renal functions, and pathohistlogicaly inspected. All cases of the cow that a renal disorder was recognized, an either β
2-m and Alb showed abnormality. In particular, urinary β
2-m was increased in the cases of interstitial nephritis and/or renal tubular nephritis, and urinary Alb was increased in the cases of glomeronephritis. Furthermore, the concentration ratio of urinary Alb and β
2-m (Ualb/ Ub2) decreased in the cases that interstitial nephritis and/or renal tubular nephritis, and Ualb/Ub2 increased in the glomeronephritis. In addition, because IAlb and/or Ib2 were showed abnormal values in the cases that showed normal values in a various renal function test, it is suggested that urinary Alb and β
2-m were more sensitive tools for renal function diagnosis. On the other hand, because creatinine index of urinary Alb and β
2-m concentration dose not receive influence of urinary volume, and they were able to test at any time for urine, therefore it is suggested that its significance for diagnosis was higher.
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