Partial Portal Vein Arterialization to Treat Toxic Acute Liver Failure in Elderly Rats.

INTRODUCTION

Toxic acute liver failure can be fatal even after liver transplantation. Since there are data only in young rats, the aim of our study was to verify the effectiveness of the increase of oxygen to the liver by partial portal vein arterialization (PPVA) in elderly rats with acute liver failure induced by carbon tetrachloride (CCl4) intoxication.

METHODS

Twenty elderly (30 months) Sprague-Dawley rats underwent a CCl4 intoxication (5 mL/kg). Animals were divided after 24 hours (n = 10 per group) to either undergo PPVA (G1, treated group) or be untreated (G2, control group). PPVA consisted of a shunt between the left renal artery and splenic vein after nephrectomy and spelnectomy. The G2 group animals underwent nephrectomy and splenectomy only. The 10-day survival was evaluated. Before euthanasia, blood samples from the portal vein were detected for blood gas analysis. Liver injury was evaluated by the serum alanine aminotransferase (ALT) and prothrombin time levels. Histology was done to evaluate the liver necrosis. Hepatocyte regeneration was assessed by the mitotic index at immunohistochemistry.

RESULTS

The PPVA has resulted in a significant increase in the oxygen partial pressure and saturation in portal blood. A survival improvement at 10 days was registered in the PPVA-treated rats (90% vs 30%; P = .0065). After 24 hours from intoxication, ALT was high in both groups. A rapid decrease of ALT was observed in G1 as compared to G2. At the same time, livers showed a severe centrolobular necrosis. In the suviving G2 rats, a moderate necrosis was present, while only a mild necrosis was observed in the G1 rats. An higher mitotic index was detected in rats treated with PPVA.

CONCLUSIONS

In our experimental study, the presence of oxygenated blood in the portal venous system following the PPVA procedure had positive effects on liver regeneration and rats' survival. The PPVA treatment had beneficial effects in elderly rats.