【作者】 赵东家；

【导师】 于为民；

【作者基本信息】 山西医科大学 ， 内科学， 2010， 硕士

【摘要】 目的：通过制备实验性糖尿病大鼠模型,观察糖尿病大鼠肾损害情况和VEGF的表达以及来氟米特干预后的变化情况,探讨治疗DN可能的作用机制,从而为临床上防治DN提供新的思路和手段。方法：将50只大鼠行右肾摘除术,两周后按随机数字表法将50只大鼠随机分为正常对照组(A组)12只及DN模型组38只。最后成DN模型36只,死亡两只。成模7d后,将成模糖尿病大鼠随机分成3组：模型对照组(B组)、来氟米特干预组(C组)和氯沙坦干预组(D组)各12只。来氟米特干预组以来氟米特5mg/kg/d灌胃给药,氯沙坦干预组以氯沙坦按20mg/kg/d灌胃给药,正常对照组和模型对照组大鼠用等量蒸馏水灌胃。成模后每两周测1次体重,测1次血糖。于实验第8周、12周末各组分别取6只大鼠用代谢笼收集24h尿,测尿蛋白定量；心内采血测肌酐(Scr)尿素氮(BUN)；解剖肾脏去除包膜、称重、取肾组织做蜡块,切片行PAS染色进行光镜观察病理改变,应用RT-PCR方法检测VEGF的mRNA,应用免疫组化的方法测定VEGF的蛋白表达。结果：(1)糖尿病大鼠肾损伤模型死亡两只,成模率96%,成模后无一只死亡。(2)本实验发现DN大鼠肾脏VEGF mRNA呈持续表达,VEGF蛋白主要分布于肾小球上皮细胞,与既往报道一致。本研究还发现在糖尿病模型组VEGF分布范围较正常大鼠组明显增大,8、12周在肾小球的表达明显增强。均说明VEGF在DN发生、发展过程中可能起到一定的致病作用。(3)来氟米特组及氯沙坦干预组通过来氟米特及氯沙坦的干预,肾重/体重、Scr、BUN及24hU-TP等生化指标均较糖尿病组有所减少,肾脏病理结构损伤减轻,VEGF蛋白表达及VEGF mRNA表达也均较糖尿病模型组减少。来氟米特干预组与氯沙坦干预组间各项指标无统计学差异,故也可证明来氟米特可能具有减少尿蛋白、保护肾脏结构与功能的作用。结论：DN时存在VEGF表达的增加,通过来氟米特干预后VEGF表达的减少,提示来氟米特具有保护DN大鼠肾脏的作用。更多还原

【Abstract】 Objective:To observe the kidney damaged conditions of diabetic rats, the expression of VEGF and the changes after intervention of leflunomide by preparing an experimental diabetic rat model so as to explore the possible mechanism of treating DN and provide new ideas and means for clinical prevention and treatment of DN.Methods:Fifty rats were given removal of right kidney. Two weeks later,50 rats were randomly divided into a normal control group (group A) with 12 rats and a DN model group with 38 rats according to the random number table. Thirty-six rats formed into the DN model and 2 rats died among them finally. After 7 days of forming model, the diabetic rats were randomly divided into 3 groups again. They were a model control group (group B), a Leflunomide intervention group (group C) and a Losartan intervention group (group D).Each group with 12 rats. The rats of the Leflunomide intervention group(group C) were given Leflunomide of 5 mg/kg/d by intragastric gavage, the rats of the losartan intervention group(group D) were administered losartan of 20mg/kg/d by intragastric gavage and the rats of the normal control group(group A) and the model control group (group B) were administered with equal volume of distilled water. The body weight and the blood glucose were measured once every two weeks. The 24h urine was collected from six rats of each group in metabolic cages in the experiment of the first 8 weeks and 12 weekends so as to measure the urinary protein quantity. Intracardial blood sampling collecting detected the Scr and BUN. Dissecting kidneys removed capsule. Weighing and taking kidney tissues made the paraffin,and then the paraffin sections were stained by PAS to observe the pathological changes by light microscopy. mRNA of VEGF was detected by RT-PCR and the VEGF protein expression was determined by immunohistochemical assay.Results:(1). There were 2 rats died in the kidney damaged model of diabetic rats and the model success rate was 96%. no one died after model formed finally.(2) The experiment showed VEGF mRNA in DN rat kidneys was continuous expression. The VEGF protein mainly distributed in glomerular epithelial cells, which accorded with past reports. The study also found that the distribution of VEGF in the diabetic model group was significantly wider than that of the normal rat group and the expression in kidney tubular of 8 and 12 weeks was markedly increased. So it suggests that the VEGF play a pathogenic role in the happening and development of DN.(3) The kidney weight/body weight, Scr, BUN,24hU-TP and other biochemical criteria in the Leflunomide group and the losartan group intervened by leflunomide and losartan decreased than those in the diabetic group. And the injuries of kidney pathology structure were milder. The expression of VEGF protein and VEGF mRNA also reduced than those in the diabetic model group. There was no significant statistical difference between the Leflunomide intervention group and the losartan intervention group. Therefore, it can also be proved that leflunomide may be of the role of reducing the urine protein to protect the structure and function of kidney.Conclusion:The expression of VEGF may increase when DN exists. While the expression of VEGF decreases when intervened by leflunomide. It indicates that leflunomide be of protective role for DN rat kidneys.更多还原