Experimental study on portal vein ligation combined with in situ splitting on liver regeneration in rats

Abstract

Objective To investigate the effect of portal vein ligation combined with in situ splitting on liver regeneration in rats. Methods Seventy-five healthy male Sprague-Dawley rats were selected and randomly assigned into sham operation group (S), portal vein ligation group (PVL) and portal vein ligation combined with in situ splitting group (ALPPS). On 1 d, 3 d, 7 d, 10 d, 14 d after operation, the hepatic regeneration rate (HRR) of right median lobe was calculated, the serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), IL-6, HGF, VEGF were detected. mRNA of IL-6, HGF, TNF-α, TGF-β was assayed by real-time PCR, and the hepatic proliferating cell nuclear antigen (PCNA) labeling index was evaluated by immunohistochemistry. Results Comparing with PVL group, the HRR of the right median lobe obviously increased on day 3, 7, 10 and 14 in ALPPS group (P<0.05), and ALT and AST level were increased on 1 d (P<0.05). On day 1 and 3, the content of serum IL-6, HGF and VEGF were all increased in ALPPS group [(70.7±14.6) pg/ml vs. (134.2±31.4) pg/ml; (0.70±0.04) ng/ml vs. (0.74±0.02) ng/ml; (82.1±12.6) pg/ml vs. (103.5±14.7) pg/ml], respectively (P<0.05). The mRNA expression of IL-6, HGF, TNF-α, TGF-β and the PCNA labeling index were also increased in ALPPS group in comparison with those in PVL group on day 1 and 3 (P<0.05). All the indexes in the two groups were all higher than those in the group S (P<0.05). Conclusions Portal vein ligation combined with in situ splitting could significantly enhance liver regeneration. The possible mechanisms were related to the inflammation reaction and stress response caused by in situ splitting and up-regulation of cytokines in the regenerating lobe after portal vein ligation combined with in situ splitting, especially IL-6, HGF and TNF-α. Key words: Liver partition; Portal vein ligation; Staged hepatectomy; Liver regeneration; Future liver volume