Influence of auxiliary graft on native liver in rat auxiliary partial orthotopic liver transplantation model

We developed a model of auxiliary partial orthotopic liver transplantation (APOLT) in the rat, and investigated influence of auxiliary graft (AG) on native liver (NL). The median lobe and left lateral lobe of the recipient's liver was resected, accounting for 70% of liver volume. The graft size was reduced by 70% hepatectomy of the donor's liver in situ, and the reversed graft was transplanted orthotopically. Anastomosis between the graft's suprahepatic vena cava and the recipient's hepatic vein was done by running suture. The cuff technique was performed for the anastomosis between the graft's portal vein and recipient's portal branch. The artery was not reconstructed. The tissue blood flow(TBF) of AG and NL was measured until 6 hours after transplantation. The blood samples and liver sections were collected, and analyzed for TNF-alpha, nitric oxide (NO), ALT, hyaluronic acid and PCNA labeling index (LI). There were no differences in the TBF between AG and NL at any time point (p = 0.467). However, the significant time-dependent changes of AG/NL ratio were observed (p = 0.013). AG/NL ratio of TBF at 1 hr and 2 hrs after reperfusion increased above 1.0 and decreased thereafter. The mean values of TNF-alpha, NO, ALT and hyaluronic acid were significantly higher in APOLT than controls of 70% hepatectomized rats at 6 hrs after hepatectomy. PCNA LI of controles were higher than that of NL (p = 0.08) and AG (p = 0.03). These findings suggest that native liver function may be deteriorated by the graft due to depriving blood flow and releasing cytokines in APOLT.