[Evaluation of liver function with 13C-labelled amino acid using hepatectomized rat model].
Using a rat model of hepatectomy, we investigated whether the severity of hepatopathy could be quantitatively measured from changes in expiratory 13CO2 levels after intravenous administration of L-[1-(13)C]phenylalanine, L-[1-(13)C]methionine or L-[1-(13)C]alanine.


METHODS
Under nembutal anesthesia, 30 mg/kg L-[1-(13)C]phenylalanine, 40 mg/kg L-[1-(13)C]methionine or 20 mg/kg L-[1-(13)C]alanine was administered to rats through the femoral vein, and expiratory 13CO2 levels were measured for 15 min. Thirty percent, 70% or 90% hepatectomy was performed. In the control group, simple laparotomy was performed.


RESULTS
The correlation coefficient between total 13CO2 output over 15 min after L-[1-(13)C]phenylalanine administration and liver weight/body weight was 0.883 (P < 0.001). The correlation coefficient between total 13CO2 output over 15 min after L-[1-(13)C]methionine administration and liver weight/body weight was 0.922 (P < 0.001). The correlation coefficient between total 13CO2 output over 15 min after L-[1-(13)C]alanine administration and liver weight/body weight was 0.902 (P < 0.0001).


CONCLUSIONS
In the breath test with intravenously administered L-[1-(13)C]phenylalanine, L-[1-(13)C]methionine, or L-[1-(13)C]alanine, hepatopathy could be quantitatively evaluated by measuring expiratory 13CO2 levels over 15 min.
Department of Surgery Division 3, Nihon University School of Medicine, Itabashi-ku, Tokyo 173-8610, Japan. yishii@med.nihon-u.ac.jp
Yukimoto
Y
Ishii
Koichi
K
Ishikawa
Satoshi
S
Asai
D000409:Alanine; D000596:Amino Acids; D000818:Animals; D001944:Breath Tests / Q000379:methods*; D002245:Carbon Dioxide / Q000032:analysis*; D002250:Carbon Radioisotopes; D006498:Hepatectomy; D008111:Liver Function Tests / Q000379:methods*; D008715:Methionine; D010649:Phenylalanine; D019275:Radiopharmaceuticals; D051381:Rats
D000596:Amino Acids; D002250:Carbon Radioisotopes; D019275:Radiopharmaceuticals; D002245:Carbon Dioxide; D010649:Phenylalanine; D008715:Methionine; D000409:Alanine