A novel method for measuring serum ornithine carbamoyltransferase.
BACKGROUND
Serum ornithine carbamoyltransferase is a diagnostic marker of hepatic disorders due to its localization in periportal mitochondria.


METHODS
We have developed a new method for the determination of serum ornithine carbamoyltransferase. It is based on the reverse reaction of ornithine carbamoyltransferase, using ornithine-ketoacid aminotransferase, Delta(1)-pyrroline-5-carboxylate dehydrogenase and glutamate dehydrogenase, which together convert citrulline through ornithine to glutamate. The glutamate is then quantitatively measured using glutamate oxidase and Trinder's reagent.


RESULTS
The results obtained by this method agreed well with those obtained using the diacetylmonoxime method as a gold standard [correlation coefficient (r) = 0.973 P<0.001]. The endogenous amino acids sensitive to this method in serum (glutamate, ornithine and Delta(1)-pyrroline-5-carboxylate) were eliminated by the initial futile reaction. The new method appears to be more accurate at low levels of ornithine carbamoyltransferase activity than the diacetylmonoxime method.


CONCLUSIONS
Here we report a new method for serum ornithine carbamoyl-transferase assay which might be useful for clinical diagnosis of hepatic disorders, including hepatic cancer.
Ishikawa
Hiroaki
H
Department of Medical Technology, Fujita Health University College, Toyoake, Aichi 470-1192, Japan. hishikaw@fujita-hu.ac.jp
Matsuzawa
Takeo
T
Ohashi
Koji
K
Nagamura
Yoichi
Y
D015415:Biomarkers / Q000097:blood; D002956:Citrulline / Q000737:chemistry / Q000378:metabolism; D005969:Glutamate Dehydrogenase / Q000378:metabolism; D005971:Glutamates / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D008107:Liver Diseases / Q000097:blood; D009952:Ornithine / Q000737:chemistry / Q000378:metabolism; D009954:Ornithine Carbamoyltransferase / Q000097:blood* / Q000378:metabolism*; D009953:Ornithine-Oxo-Acid Transaminase / Q000737:chemistry / Q000378:metabolism; D011762:Pyrroline Carboxylate Reductases / Q000378:metabolism; D012016:Reference Values; D015203:Reproducibility of Results
D015415:Biomarkers; D005971:Glutamates; D002956:Citrulline; D009952:Ornithine; D005969:Glutamate Dehydrogenase; D011762:Pyrroline Carboxylate Reductases; D009954:Ornithine Carbamoyltransferase; D009953:Ornithine-Oxo-Acid Transaminase