Function of reduced-size liver transplant in the rat

Re-Arterialized Rat Partial Liver Transplantation with an in vivo Vessel-Oriented 70% Hepatectomy

Split liver transplantation and living liver donor liver transplantation were developed in the clinic to utilize liver organs in a more efficient manner. To better understand the mechanism behind these surgical procedures, a rat partial liver transplantation (PLTx) model was established for relevant surgical studies. Because of the complexity of the rat PLTx model, a protocol with detailed descriptions is required. An article published previously reported a protocol in which ex vivo hepatectomy was used to achieve 50% rat PLTx. In contrast to this protocol, we introduced a re-arterialized PLTx with an in vivo 70% hepatectomy. An updated vessel-oriented hepatectomy was incorporated into the rat PLTx to refine the microsurgical procedure. The portal veins and hepatic arteries of the left lateral lobe and the median lobe were individually dissected and ligated before removal of the liver parenchyma, thereby decreasing the probability of bleeding in the remnant liver stump. Furthermore, an end-to-side vessel anastomosis between the common hepatic artery and the enlarged proper hepatic artery was introduced to re-arterialize the hepatic artery. By using this end-to-side vessel anastomosis technique, the diameter of the anastomosis was enlarged, thereby decreasing the difficulty of hand suture and maintaining a high rate of anastomotic patency. Moreover, the cuff anastomosis of the infrahepatic vena cava was slightly modified. A section of circumferential liver parenchyma around the vena cava of a recipient was preserved during cuff anastomosis to maintain the three-dimensional shape of the vascular lumen. This section of liver parenchyma was removed after completing the anastomosis. With this modification, the step involving placement of stay sutures was omitted, thereby further shortening the cuff anastomosis time. By using this protocol of rat PLTx, a low liver enzyme level, an intact liver lobular architecture and a high survival rate were achieved after microsurgery.

Successful transplantation of a 20% partial liver graft in rats: a technical innovation

BACKGROUND

Graft-size disparity negatively impacts the postoperative outcome in the setting of adult-to-adult living donor liver transplantation.

MATERIALS AND METHODS

As a model for partial liver transplantation in rats using a minimized graft volume, we orthotopically transplanted a 20% reduced-size liver with the two-cuff method. Blood chemistry, graft weight restoration, and labeling indices of 5-bromo-2'-deoxyuridine were estimated.

RESULTS

We achieved 100% 2-week survival. Hepatic mass was restored rapidly with early normalization of biochemical parameters, although albumin synthesis capacity required more time to recover.

CONCLUSION

This technique has great potential for research as well as a therapeutic approach to regeneration and functional recovery of small liver grafts under various posttransplant circumstances.