A novel auxiliary partial orthotopic liver transplantation model in rats

Background: Although auxiliary partial orthotopic liver transplantation (AP OLT) has become a well-accepted procedure recently, a practical experiment model in APOLT using small animals has yet to be developed. Methods: Male L ewis rats were used for both donors and recipients. An auxiliary partial gr aft was obtained by ex vivo resection of the donor right and caudate lobes, and was transplanted orthotopically into the recipient after resection of the recipient medial and left hepatic lobes. Portal vein and hepatic duct r econstructions were by the cuff technique, and supra- and intrahepatic vena cava were sutured continuously. Operative outcomes, serum chemistry, liver tissue blood flow, angiographic and histopathological findings were then e xamined. Conventional orthotopic liver transplantation (OLT) procedures wer e also undertaken as a control. Results: One-day, 1-week and 1-month surviv al rate of APOLT group was 100, 85 and 85%, respectively. AST in the APOLT group on the Ist postoperative day was significantly higher than in the OLT group. No significant differences were recognized in serum albumin and tot al bilirubin levels between the two groups. Although the portogram of an AP OLT rat showed slight narrowing at the cuff anastomosis site, both the graf t and the native liver were opacifled similarly. The liver tissue blood flo w on the 5th postoperative day in the native liver and the graft returned t o as high as 95 and 74% of the values on laparotomy, respectively. Histolog ical examinations of the auxiliary graft 1 month after transplantation show ed mild ductular proliferation and mononuclear cell infiltration around the portal triads. Conclusion:This novel APOLT model in rats allows practical and reproducible results, and may be of value in the basic study of APOLT p rocedures. Copyright (C) 2000 S. Karger AG. Basel.