[Apoptosis and the expression of Bax and Bcl-2 in the penis of diabetic rats].

OBJECTIVE: To investigate the relationship between apoptosis and the expression of Bcl-2 and Bax in the penis cavernosal tissues of diabetic rats. METHODS: Fifty male adult Wistar rats were divided into two groups: 10 as normal control and 40 used to induce diabetes by intravenous injection of alloxan (AXN) (50 mg/kg). After 8 weeks, their penises were harvested. Apoptosis was evaluated by means of terminal deoxynucleotidyl transferase mediated d-UTP nick end labeling (TUNEL). Immunohistochemistry was employed to detect the protein of Bcl-2 and Bax. RESULTS: Compared with those in the control group, apoptotic cells were more in number (P<0.01) and the expression of Bcl-2 was absent in the penis cavernosal tissues of the diabetic rats. However, there was upregulation of Bax and decrease in Bcl-2/Bax ratio in the diabetic group. CONCLUSION: The high rate of apoptosis in diabetic rats may play a role in the pathophysiology of erectile dysfunction. The change in Bcl-2 and Bax activities may be responsible for apoptosis in diabetic penis erectile tissues.