糖尿病大鼠阴茎海绵体细胞凋亡与Bcl-2和Bax基因表达

目的 :观察糖尿病 (DM)大鼠阴茎海绵体细胞凋亡、Bcl 2和Bax的基因表达及两者的相关性。　方法 :成年雄性Wistar大鼠 5 0只 ,随机分为正常对照组 (NDM组 ) 10只和造模组 4 0只。造模组以 5 0mg/kg尾静脉注射 2 %四氧嘧啶 (AXN) ,未发生DM者 ,为AXN组 ;成为DM模型者为DM组。大鼠饲养 8周后处死并取阴茎海绵体 ,用原位末端标记法 (TUNEL)检测细胞凋亡 ,用免疫组化方法检测Bcl 2、Bax的基因表达。　结果 :DM组大鼠较NDM组大鼠阴茎海绵体凋亡细胞数明显增多 (P <0 .0 1) ,Bax表达亦增强 (P <0 .0 1) ,Bcl 2表达减弱 (P <0 .0 1) ,Bcl 2 /Bax比值降低。　结论 :DM大鼠阴茎海绵体细胞凋亡率增加 ,细胞凋亡可能是糖尿病性勃起功能障碍的发病机制之一 ,Bcl 2和Bax可能参与了DM大鼠阴茎海绵体细胞凋亡的基因调控。

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.