Suppression of liver regeneration affects hepatic graft survival in small‐for‐size liver transplantation in rats

Aim: Small‐for‐size liver transplantation (SFSLT) often results in hepatic graft failure and decreased survival. The present study was aimed to investigate the possible mechanism of hepatic graft failure in SFSLT in rats. Methods: Rat models of full‐size orthotopic liver transplantation, 50% partial liver transplantation and 30% partial liver transplantation were established. Proliferative responses of the hepatic graft were evaluated by immunohistochemical staining and western blotting. Apoptosis‐, inflammatory‐, anti‐inflammatory‐ and growth factor‐related genes were screened by quantitative reverse transcription polymerase chain reaction. Activities of transcription factors of AP‐1 and nuclear factor (NF)‐κB were analyzed by electrophoretic mobility shift assay. Results: A 30% partial liver transplant not only resulted in marked structural damages to the hepatic graft, but also showed the lowest 7‐day survival rate. In addition, sup pressed expressions of proliferating cell nuclear antigen (PCNA) and cyclin D1 by immunohistochemical staining and decreased expressions of cyclin D1 and p‐c‐Jun by western blotting were detected. Downregulated expressions of Bcl‐2, Bcl‐XL, interleukin (IL)‐6, IL‐10, IP‐10 and CXCR2, upregulated expression of tumor necrosis factor‐α, and decreased levels of AP‐1 and NF‐κB were also found following 30% partial liver transplantation after reperfusion. Conclusion: Liver regeneration is remarkably suppressed in SFSLT. The significant changes of intra‐graft gene expression described above indicated that ischemia reperfusion injury would be severe in 30% partial liver transplantation. The capability of liver regeneration secondary to ischemia reperfusion injury might determine hepatic graft survival in SFSLT.