실험적으로 정계정맥류 및 수신증을 만든 쥐에 있어서 p53 및 ɤ- H2AX의 발현

Abstract

Purpose: Since sperm DNA damage-related apoptosis caused by reactive oxygen species (ROS) is arising concerns with abnormal spermatogenesis and renal parenchymal damage in urologic part, we investigated the changes of the DNA damage-related regulatory proteins during testicular germ cell apoptotic responses induced by experimental varicocele in rats and renal parenchymal cell apoptotic responses induced by partial ureteral obstruction. Materials and Methods: A total of 16 of 12-weeks old Sprague-Dawley rats underwent experimental left varicocele. Out of the 16 rats, we operated 12 rats for their varicocele and the other 4 rats for their sham-operated controls. The testis tissues were prepared on the first, third, and fourth week after the experimentally induced varicocele. The levels of p53 and gamma-H2AX were examined by immunohistochemistry and western blot analysis. 16 Sprague-Dawley rats that were 7∼8 weeks old were used. Partial ureteral obstruction was induced in 12 rats. And for the other 4 rats, a sham-operation was done as a control. The hydronephrosis-induced rats had their right kidney removed after 1, 2 and 3 weeks and the sham-operated rats underwent nephrectomy after 3 weeks. Those removed tissues were examined with immunohistochemical staining and western blot to confirm the degree of expression of p53 and γ-H2AX. Results: Immunohistochemical staining of the left testes in varicocele-induced rat showed that the expression of p53 and phosphorylation of H2AX did not begin 2 weeks postoperatively, but remarkable results were observed at 3 and 4 weeks. Both testes of the varicocele-induced rat showed the expression of p53 and phosphorylation of H2AX at 4 weeks, with the left testes being more distinctive in immunohistochemical staining compared to the right. Western blot of the left testes in varicocele-induced rat also showed unclear expression of p53 and γ-H2AX at 2 weeks. Considerable distinction was seen at 3 and 4 weeks compared to the control group. The expressions of p53 and γ-H2AX caused by hydronephrosis in the rat increased as time passed, and these expressions of controls were in a low level or they were negative. These results were similar with the results of the immunohistochemical staining and western blot Conclusions: This study is shown that the protein expressions of γ- H2AX and p53 are increased, and these expressions are the DNA damage-related factors in the varicocele and renal parenchyma of hydronephrosis induced rats. We suggested the possibility that DNA double strand breaks(DSBs) might be the main mechanism that induces abnormal spermatogenesis in experimental varicocele and renal parenchymal damage under the condition of hydronephrosis