The impact of hepatic denervation on the accumulation of hepatic progenitor cells during liver regeneration in rats.

BACKGROUND/AIMS: All autonomic hepatic nerves are transected following liver transplantation. Recent studies have shown the relationship between an inhibition of autonomic nerves and the accumulation of hepatic progenitor cells (HPC). This study aims to elucidate the influence of hepatic denervation on the accumulation of HPC in the process of liver regeneration. METHODOLOGY: Male Sprague-Dawley rats underwent hepatic denervation. Immediately after either denervation (DN group, n=30) or a sham operation (control group, n=30), a two-thirds hepatectomy was performed, and these were sacrificed chronologically. An immunohistochemical analysis of HPC was performed with a mouse monoclonal OV6 type antibody. RESULTS: The liver per body weight ratio gradually increased in both groups. On postoperative day (POD) 7, the DN group showed a significantly higher ratio. The HPC expression gradually increased in both groups. The maximal HPC number was observed on POD 7 in the DN group and on POD 3 in the control group. Although there was no significant difference in the HPC numbers between the DN and control group until POD 3, the number of HPC were significantly higher in livers of the denervated rats than in those of the sham operated rats between POD 5 and 14. CONCLUSIONS: The hepatic autonomic nerves were thus suggested to play an important role in the accumulation of HPC during liver regeneration in rats.