微血管病变在糖尿病膀胱病变中的作用的研究

目的探讨微血管病变在糖尿病膀胱病变中的作用及其机制。方法构建STZ．糖尿病大鼠模型；通过尿流动力学指标对膀胱功能进行评价；位用免疫组化方法检测膀胱组织中eNOS蛋白的表达水平，采用透射电镜观察膀胱微血管超微组织结构改变，确定其与膀胱功能的相关性。结果尿流动力学检查显示糖尿病大鼠的最大膀胱容量、单次排尿量、残余尿量均呈时间依赖性显著增加（P〈0．01）膀胱排尿率亦显著下降（P〈0．05）。糖尿病大鼠膀胱组织中eNOS蛋白的表达呈时间依赖性增加，与膀胱排尿率负相关。电镜结果显示膀胱微血管的超微组织结构出现进行性的改变，包括广泛的线粒体破坏和溶酶体聚集。结论内皮型一氧化氮合成酶eNOS介导的内皮功能失调和微血管损伤，可能参与了糖尿病膀胱病变的发生发展，可以作为一个形态学的评价和诊断指标。

Role of Ultra-structure Change of Bladder Micro Vessels in the Pathogenesis and Development of Diabetic Cystopathy in a STZ-induced Diabetic Rat Model

Objective To explore the possible role of ultra-structure change of bladder micro vessels in the pathogenesis and development of diabetic cystopathy.Methods Diabetic model was established by a single intra- peritoneal injection of 60mg/kg STZ in male Sprague-Dawley rats. Rats were divided into 3 groups： normal control, diuresis control and diabetes groups.Examinations were performed at 6W and 12W after injection of STZ.Cystometry was taken to evaluate the bladder function;Ultra-structure changes of bladder micro vessels,especially the endothelial cells,were carried out by electro-microscope.Expression levels of eNOS protein were assessed by immunohistochemistry assay and its correlation with bladder function index was analyzed.Results The result of cystometry revealed that bladder capacity,single voiding volume and post-voiding volume of diabetic group were significantly increased compared with normal and diuresis control groups in a time dependent manner （P〈0.01） while voiding efficiency of diabetic group was significantly decreased（P〈0.05）.The expression of eNOS was found only in bladder vessels by IHC.Compared with normal rats,the diabetic rats showed significantly stronger stain of eNOS. We observed remarkable alteration of bladder microvessel under electro-microscope characterized by swollen endothelial cells with disappeared mitochondrial cfistae,ruffled nucleus,and condensed chromatin.There was increased number oflysosome while decreased ribosome and endoplasmic retieulum in the endothelial cells.Conclusion The ultra-structure change of bladder micro vessels mediated by up-regulated expression of eNOS protein may be involved in the pathogenesis and development of diabetic cystopathy.