Histologic Changes, Hsp 70 and bcl-2 Expression and Apoptosis Following Piezoelectric Extracorporeal Shock Wave Treatment on Immature Rat Testis

Park, Won Chan; Yang, Sung Hak; Yoon, Hye Kyoung

Abstract

PURPOSE: The aim of this study is to evaluate the sequential histologic changes and spermatogenesis of the testis after extracorporeal shock wave treatment (ESWT).
MATERIALS AND METHODS
ESWT to right testis was applied on total 48 immature, 5-week-old Sprague Dawley rats. The rats were sacrficed immediately, at 1 day, 3 days, 1 week, 2 weeks and 4 weeks after ESWT, and each group consisted of 8 rats including 2 rats as control (without ESWT). Histologic changes of both testes were examined, and serial three or more parafin sections were obtained, and immunohistochemical stains for bcl-2 and Hsp 70 and TUNEL method for apoptosis were performed.
RESULTS
Hemorrhage and destruction of seminiferous tubules which appeared immediately after ESWT were maximal at 1 day after ESWT and were seen absorption and atrophy at 1 week after ESWT. Even regenerating tubules were found at 2 weeks after ESWT, no significant histologic difference between both testes experimental and control groups were seen except for some regenerating tubules. The right testicular tissues, remote from the ESWT-targeted area, showed preserved spermatogenesis since the age of 5 weeks 3 days, and was presented no significant difference between experimental and control groups. Hsp 70 and bcl-2 expression and apoptosis were maximal at 1 day after ESWT and persisted to 3 day after ESWT. Weak and focal expression were noted at 1 week after ESWT, and mostly disappeared at 2 weeks after.
CONCLUSIONS
Spermatogenesis of right testis except the targeted area was not diffrent compared with that of left testis and control group. Hsp-70 expressin, which limits tissue destruction after injury, was immediately appeared for defense mechanism, and hemorrhage and tissue destruction following ESWT seemed to be due to apoptosis controlled by bcl-2 expression.