ABSTRACT
PURPOSE: This study was performed to evaluate the functional and histological changes following orthotopic testicular transplantation. A new microsurgical technique was used for the transplantation. MATERIALS AND METHODS: Recipient rats were castrated, and microsurgically-removed testes from adult rats were utilized for orthotopic transplantation. Animals were divided into three groups:(1) the control group(n=6);(2) the castrated group(n=6);(3) the orthotopic testis transplantation group (n=12). In order to identify the survival of the testis after transplantation, testicular scans and histopathological examinations were performed. RESULTS: The following results were obtained from examination of transplanted testes: 1. Histopathologic findings. Excluding 2 transplanted rats which demonstrated ischemic necrosis, the testes of the other 10 transplantated rats showed almost normal histologic findings. 2. Testicular scan. Testicular scan was effective to differentiate the successfully transplanted testes from the testes with ischemic necrosis. CONCLUSIONS: These results demonstrate that orthotopic transplantation has a higher possibility of graft survival, and testicular scan is aneffective method to confirm the survival of transplanted testes. In addition, newly-developed orthotopic transplantation animal models could be used for research on the hypothalamus-pituitary-testis axis. The orthotopic transplantation technique could alsobe used as a new therapeutic method for congenital and acquired hypogonadism patients.