title: Evaluation of remnant liver function using 13C-breath tests in a rat model of 70% partial hepatectomy.
abstract: OBJECTIVE
  A 13C breath test was applied to evaluate the early stage of postoperative liver function after hepatectomy. It was examined in comparison with functional and morphological recovery.
  
  
  METHODS
  Rats were subjected to 70% partial hepatectomy (H group) and control group (S group). Expired air, blood and remnant liver tissue were collected at 12, 24, 48 and 72h, and 7 and 14 days postoperatively. Phenylalanine and leucine were used as the 13C-labeled substrates. The 13CO2 was collected until 120min. The mean values of the H and S groups were compared using the highest mean level of 13CO2 excreted in breath (Cmax). The liver regenerative ability was evaluated by Ki-67.
  
  
  RESULTS
  In the 13C-phenylalanine breath test, the Cmax value tended to be lower for the H group 12h postoperatively (p=0.06). Cmax was significantly lower for the H group 24h postoperatively (p<0.05). Both groups showed equal recovery at 48h postoperatively. In the 13C-leucine breath test, both groups had no significant difference after hepatectomy. The peak of Ki-67 positive rate is estimated to be at 52.8h postoperatively, meaning that the time difference was only approximately 5h between the peak time of Ki-67 positive rate and the 13C-phenylalanine breath test.
  
  
  CONCLUSIONS
  These results strongly support that the 13C-phenylalanine breath test can become a non-invasive indicator to evaluate the early stage of postoperative liver function after hepatectomy.
authors.affiliation: Department of Surgery, Toho University, Tokyo, Japan. y-miura@med.toho-u.ac.jp
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Miura
authors.forename: Naohiro
authors.initials: N
authors.lastname: Washizawa
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Urita
authors.forename: Tsunehiko
authors.initials: T
authors.lastname: Imai
authors.forename: Hironori
authors.initials: H
authors.lastname: Kaneko
mesh_terms: D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D001219:Aspartate Aminotransferases / Q000097:blood; D001663:Bilirubin / Q000097:blood; D015415:Biomarkers / Q000097:blood; D001944:Breath Tests; D002245:Carbon Dioxide / Q000378:metabolism*; D002247:Carbon Isotopes; D006498:Hepatectomy; D019394:Ki-67 Antigen / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000097:blood; D007930:Leucine / Q000008:administration & dosage / Q000378:metabolism; D008099:Liver / Q000378:metabolism / Q000473:pathology / Q000601:surgery*; D008111:Liver Function Tests; D008115:Liver Regeneration; D008297:Male; D023421:Models, Animal; D018482:Muscle, Skeletal / Q000378:metabolism; D009929:Organ Size; D010649:Phenylalanine / Q000008:administration & dosage / Q000378:metabolism; D011237:Predictive Value of Tests; D051381:Rats; D011916:Rats, Inbred F344; D013997:Time Factors
chemical_list: D015415:Biomarkers; D002247:Carbon Isotopes; D019394:Ki-67 Antigen; D002245:Carbon Dioxide; D010649:Phenylalanine; D007770:L-Lactate Dehydrogenase; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase; D007930:Leucine; D001663:Bilirubin