Orthotopic forelimb allotransplantation in the rat model.

In this report, we present a rat orthotopic forelimb allotransplantation model. Eight forelimbs were transplanted from Brown Norway rats to Lewis rats. Axillary vessels of transplant were used as the vascular pedicles, which were anastomosed to the external jugular vein and common carotid artery of the recipient rat. The ulnar, radial, and median nerves were also repaired. Among rats, a tapered dose of cyclosporine was administered in five rats. In other three rats, no immunosuppressive therapy was given. The viability and signs of rejection of transplanted forelimbs, sensation recovery, bone healing, and histology were assessed up to the 90 postoperative day. All of rats but one survived surgery. All of transplanted forelimbs survived. In the rats treated with cyclosporine the transplanted forelimbs achieved long-term survival with motion and sensation recovery. On 90 day after surgery, bone healing was achieved. There was no sign of rejection in histology. In the rats without cyclosporine treatment, the transplanted forelimbs experienced tissue necrosis started from day 12 postoperatively. This experimental study showed the feasibility of orthotopic forelimb allotransplantation in the rat model. © 2015 Wiley Periodicals, Inc. Microsurgery 36:672-675, 2016.