Multiorgan transplantation in the rat: development of a new microsurgical model.

Although transplantation of multiple abdominal viscera (MOTx) has been performed in humans, reproducible animal models and extensive laboratory work are needed to explore the physiological and immunological aspects of this new transplant procedure. We therefore developed a microsurgical model that allows en bloc transplantation of three major abdominal viscera. Using isogeneic rat strain combinations, 30% of the liver, pancreas, and duodenum and a segment of small bowel (SB) were heterotopically transplanted. A segment of aorta that included the celiac axis and the superior mesenteric artery provided the blood supply to the graft. Venous outflow occurred via the graft suprahepatic vena cava into the recipient's infrahepatic vena cava. The graft SB was anastomosed to the native SB. After a training period (N = 15), we could achieve a success rate of 83% (N = 23). Mean operation time was 105 minutes. Macroscopic and microscopic appearance of transplanted organs was normal. This study documents the feasibility of MOTx in the rat and provides a microsurgical model that should facilitate preclinical experimental research in this area.