The characteristics of acute rejection after limb allotransplantation in rats--an experimental study.

To study the characteristics of acute rejection after limb allotransplantation, 29 male Sprague-Dawley rats were randomly divided into 2 groups, with 15 rats in control group and 14 rats in experimental group. Each rat in control group underwent limb replantation. Each rat in experimental group received limb transplantation from Wistar rat. No immunosuppressive drugs were used after operation. The circulation of the transplanted limb, time and signs of rejection, histopathological changes in the tissues of the limb graft when rejected and survival time of limb grafts were evaluated. In the control group, no signs of rejection were observed, the circulation of each replanted limb was normal, it could survive for a longer time. The experimental group showed clinical signs of rejection (sub dermal edema and erythema) after a mean time of 3.36+/-1.15 days, and the mean survival time of the allografts was only 7+/-0.78 days. Histopathological examination showed most violent rejection reaction in skin. It is concluded that with Wistar-to-SD limb transplantation without use of immunosuppression, rejection of the grafts would occur after a mean time of 3.36+/-1.15 days; the earliest signs of rejection were edema and erythema of the skin, skin being the most representative component of limb graft rejection.