The Study Of Modification On The Technique Of Testicular Autotransplantation In Dogs And Its Influence On Grafted Testes

Objective: (1) To modify technique in making testicular autotransplantation modle in dogs and improve operation successful rate.(2)To investigate the influence of vascular anastomosis on transplanted testes and further improve the successful rate of testicular homotransplantation by ruling out the other interference such as ischemia-reperfusion injury, postoperative rejection and immunosuppressive agents. As well as it also intended to provide a reliable experimental platform for research on changing regularity of endocrine secretion and spermatogenesis of the transplanted testes.Methods: (1) Surgical technique of perfusion and detachment of the testis were modified and 30 cases of testicular autotransplantation were performed using an end-to-side anastomosis of the spermatic vessels with a cuff of abdomial aorta or inferior vena to the external iliac vessels. (2)Thirty-six male mongrel dogs were divided into control group and autotransplantation experimental group randomly. The left testis of 6 dogs in control group were removed. However after hemicastration, modified testicular autotransplantations were performed on the right side of 30 dogs in experimental group. The survival condition was observed and the patency was assessd by imaging examinations including DSA and color Doppler ultrasound. Simultaneously, histological examinations were observed and the postoperative serum levels of FSH, LH and T were determined in both groups .Results: (l)After 30 testicular autotransplantations were performed, we overcame the following key steps including testis perfusion, detachment of spermatic artery from main vessels and vessel anastomosis. The successful rate reached 90%(27/30) and the time of heat ischemia, cold ischemia, anastomosis of spermatic vessels and total operation was(4.5±0.9) minutes, (50.0±5.0) minutes, (35.5±5.5) minutes and (3.5±0.5)h respectively.(2) No significant differences of testicular weight, the diametre of seminiferous tubules, the number of Leydig cell and diametre of the Leydig cell nucleus were observed between two groups 8 weeks after operation (P>0.05). Compared to preoperative level, LH were significantly higher in both groups(P<0.05), however FSH and T without obvious changes. No significant differences of the postoperative level of FSH, LH and T at the same time between groups and at the different times inside the group were found (P>0.05). DSA and color Doppler ultrasound manifested good patency of the autograft.Conclusions: (1) A stable and feasible model of testicular autotransplantation wasestablished owing to modifications on the surgical technique by lowering the difficulty and shortening the operating time with improved operation successful rate under naked eyes. As well as it provide a reliable experimental platform for research on changing regularity of endocrine secretion and spermatogenesis of intraabdominal testes after autotransplantation. (2) The successful rate of testicular autotransplantation was improved due to modification on surgical technique without significant influence on endocrine secretion and spermatogenesis of the transplanted testes. The approach approximately simulated the procedure of testicular homotransplantation in testis perfusion, detachment of spermatic artery and vascular anastomosis. And it provided a reliable experimental and clinic platform for further research on autogeneic and homologous testicular transplantation.