Ultrastructural study of severe testicular damage following acute scrotal thermal injury.

Aim: The scrotum provides an appropriate environment for the testicles that is essential for spermatogenesis. The aim of this study was to investigate the severity of ultrastructural damage to the testicles after acute thermal injury.

Materials And Methods: Twenty male Sprague-Dawley rats weighing 250+/-20g were randomly divided into four groups of five rats each (10 testicles in each group). In the sham group, animals were anesthetized, and both testicles were removed through a lower transverse abdominal incision. For animals in the burn induction group, a container filled with boiling water was used. For the T30 group, the scrota were in contact with steam from the boiling water for 30s. This procedure was the same for the other two groups: the T60 group (60s of steam contact) and the T90 group (90s of steam contact). Skin biopsies of scrota and excisional biopsies of both testicles were taken 1h after burn. Specimens were prepared for immunohistochemical and transmission electron microscopic examinations. Apoptotic and proliferative activity in the testicles and epidermal and dermal damage to the skin were measured.

Results: Histopathological examination indicated increasing epidermal and dermal damage to the skin in parallel with the length of contact between the scrota and the steam. Increased apoptotic activity was observed in animals after 30s, testicular degeneration began at 60s, and a diffuse degeneration was observed at 90s with a high rate of apoptosis (P<.005).

Conclusion: Our findings demonstrate that thermal trauma to scrotal skin directly affects proliferation, the occurrence of apoptotic and necrotic cell death of spermatogenic seria, Sertolli and Leydig cells in testicles. Attempts to protect the testicles from severe thermal damage are essential, when the scrotal skin is affected by the burn.