Effect of portal vein ligation on tumor growth and liver regeneration in rat cirrhotic liver lobes

The aim of the present study was to investigate the effect of portal vein ligation (PVL) on the tumor growth rate and liver regeneration in rat cirrhotic liver lobes. A total of 45 male Wistar rats were randomly divided into PVL, hepatic tumor (HT) and HT + PVL groups (n=15 per group). Liver regeneration and tumor growth in ligated and non-ligated lobes were evaluated prior to and following PVL. In addition, serum alanine transaminase, total bilirubin levels and liver tissue samples were evaluated. The results indicated that PVL induced apparent hypertrophy in normal and HT rats. However, the ratio of non-ligated lobes to total liver weight or body weight in the HT + PVL group was significantly lower when compared with the PVL group (P<0.05). Compared with the HT group, the tumor growth rate in the ligated lobes of the HT + PVL group significantly increased (P<0.05). However, tumor growth in the non-ligated lobes exhibited no statistically significant difference between the HT and HT + PVL groups. In addition, Knodell scores indicated that fibrosis was more apparent in the non-ligated lobes of the HT + PVL group when compared with the HT group (P<0.05). Therefore, tumor growth was accelerated in ligated lobes following PVL, but not in non-ligated lobes. PVL also induced liver regeneration in cirrhotic liver lobes with lower efficiency than that in the non-cirrhotic lobes. However, hypertrophy in the contralateral cirrhotic lobes appeared to be non-functional.