糖尿病大鼠神经系统内脑源性神经生长因子的表达与阴茎勃起功能障碍的关系

目的:观察糖尿病(DM)大鼠神经系统内脑源性神经生长因子(BDNF)阳性神经元或神经纤维的表达,探讨BDNF与糖尿病性阴茎勃起功能障碍(ED)的相关性。方法:SD大鼠腹腔注射链脲佐菌素建立DM大鼠模型(DM组),分别于造模1、2、3、4个月注射阿扑吗啡(APO)作阴茎勃起功能试验,然后取糖尿病及相应月龄正常大鼠(对照组)的脑、腰骶段脊髓、胸腰段交感干、阴茎和前列腺,用免疫组织化学法和免疫荧光法显示BDNF阳性神经元和神经纤维。图像分析BDNF阳性细胞数及灰度。结果:糖尿病2个月时,DM大鼠阴茎勃起实验中阴茎勃起次数与对照组相比差异有显著性(P<0.05),3个月和4个月差异有极显著性(P<0.01)。糖尿病1个月时,大脑皮质、腰骶段脊髓、胸腰段交感干、阴茎和前列腺BDNF阳性神经细胞及纤维比对照组明显减少(P<0.05),随着病程延长下降更明显(P<0.01)。结论:糖尿病性早期神经系统内出现BDNF减少,BDNF的减少与糖尿病性ED的发病密切相关。

Correlation Between Brain-derived Neurotrophic Factor Expression in the Nerve System and Erectile Dysfunction in Diabetic Rats

Objective: To observe the correlation between brain-derived neurotrophic factor (BDNF) expression in the nerve system of diabetes mellitus (DM) rats and diabetic erectile dysfunction (ED). Methods: DM rats were induced by injecting streptozotocin and erectile function test was done by injecting apomorphine (APO) at 1 month, 2 months, 3 months and 4 months. Then the brain, lumbosacral spinal cord, thoracic and lumbar sympathetic trunks, penis and prostate were taken from the diabetic and normal rats of the same age. The BDNF positive neurons and nerve fibers were shown by immunohistochemistry or fluorescence immunohistochemistry. The number and the grey density of BDNF positive cells and fibers were detected by image analysis. Results: Compared with the control group, the erection frequency of the DM rats decreased at 2 months (P< 0.05 ), and significantly at 3 and 4 months (P> 0.01 ), and the BDNF positive neurons and nerve fibers in the cerebral cortex, lumbosacral spinal cord, thoracic and lumbar sympathetic trunks, penis and prostate of 1-month DM rats were reduced (P< 0.05 ). As time went on, BDNF declined progressively. Conclusion: BDNF decreases in the central and peripheral nerve system in the early stage of diabetes mellitus, wich is closely correlated with diabetic ED.