Reproducible porcine model for kidney allotransplantation of low weight miniature pig.

Background: Multiple porcine models have been established to study the mechanisms regarding kidney transplantation. With the development of xenotransplantation, the demand for a low weight miniature pig model has been increasing. A reliable and reproducible surgical technique to establish these models, and to address possible obstacles, has not been sufficiently defined in detail. The goal of the present study was to develop and optimize a low weight miniature pig porcine kidney transplantation model, including a comprehensive surgical description. Methods: Eight male Bama miniature pigs (12-15 kg) were randomly chosen as kidney donors and, to facilitate investigation of the transplanted kidney, had undergone contralateral nephrectomy. The procured kidneys were perfused with iced saline then immediately cold stored in the University of Wisconsin preservation solution. The recipients were randomly allocated to left-to-right or right-to-right groups. Serum creatinine and urine volume were recorded post-transplantation, and the pigs underwent euthanasia at seven days post-transplantation. Results: All eight pigs showed functioning grafts, immediately producing urine post-transplantation. The serum creatinine level increased the following transplantation gradually and reached a peak on the day of euthanasia. One renal artery thrombosis and one ureterovesical entrance stenosis were observed in the right-to-right group. No complications were observed in the left-to-right group. Conclusions: We developed and optimized a reproducible porcine kidney transplantation model in the low weight miniature pig. Moreover, we addressed and emphasized critical points of the left-to-right transplantation surgery and detailed the anatomic techniques to avoid stenosis of blood vessels and prevent ureterovesical stricture.