Division of the genitofemoral nerve in unilateral cryptorchid rats.

The long-term effect of dividing the genitofemoral nerve supply to the undescended testis in naturally cryptorchid rats is reported. 20 male Buffalo rats with an undescended right testis, noted at the age of 30 days, were used for the investigation. 20 healthy animals served as controls. The abdominal division of the right genitofemoral nerve was performed in 10 cryptorchid and 10 healthy animals at the age of 40 days. The animals were mated at 150 days of age. Both testes were removed at 180 days of age. In each excised testis the testicular weight and seminiferous tubular diameters were measured, and the maturity of the germinal epithelium was determined using the Johnsen testiscular biopsy score. The experiment showed that in 70% of the nonoperated cryptorchid rats, both testes were affected at the age of 180 days, and 90% of these animals were infertile. In the operated cryptorchid rats, the contralateral descended were not damaged, and 60% of these animals were fertile. The division of the genitofemoral nerve in healthy animals had no effect. The results suggest that neural transmissions might play a role in the damage to the descended testis in unilateral cryptorchidism. This observation requires further investigations.