Abstract: | In 40 male adult rats on unilateral torsion of the spermatic cord was initiated by operation. In the first group (4 x 5 animals) the testes were removed after 3, 6, 12, 24 hours. The treatment of the animals in the second group (4 x 5 animals) was untwisting of the torsion after 3, 6 12, 24 hours. Three months later both testes were removed. Histological and enzymehistochemical results are as follows: 1. The extend of acute damage to the affected testis depends on the length the torsion lasted. 2. The delay of time of untwisting the testis probably does not influence the degree of later regeneration. 3. Even short duration of torsion of the affected testis results in damage to the contralateral testies. |