大肠埃希菌感染大鼠急性肾盂肾炎MMP-2与MMP-9及TGF-β1水平

Study on the changes of MMP-2,MMP-9 and TGF-β1 levels in acute pyelonephritis model rats infected by Escherichia coli

目的利用大肠埃希菌感染致大鼠肾盂肾炎,探讨肾盂肾炎模型大鼠肾脏状况及基质金属蛋白酶-2(MMP-2)、基质金属蛋白酶-9(MMP-9)、转化生长因子-β1(TGF-β1)水平变化。方法采用大肠埃希菌菌液膀胱灌注法制备急性肾盂肾炎模型大鼠;将大鼠分为空白组(B)、对照组(C)、感染5天(M1)、感染10天(M2)、感染15天(M3)5个试验组,分别于试验结束时观察各试验组大鼠健康状况、肾脏组织学指标,并测定各试验组大鼠体质量、双肾重量、膀胱液和肾脏菌落数、炎症细胞数量,测定MMP-2、MMP-9、TGF-β1蛋白表达水平,及MMP-2、MMP-9、TGF-β1 mRNA水平。结果M1、M2、M3试验组的模型大鼠健康状况和肾脏组织学指标均低于B、C试验组大鼠,M1、M2、M3试验组大鼠活跃度降低,食欲不振,抓捕时反抗较无力,肾脏表面苍白且出现瘢痕,纵切面皮髓分界线模糊,肾盂肾盏变形,肾盂黏膜有炎症细胞浸润;模型组大鼠体质量、细菌菌落数、炎症细胞数目与B、C组大鼠存在显著差异(P<0.05),且随着感染天数增多,细菌菌落数与炎症细胞数目呈增长趋势;M1、M2、M3试验组大鼠肾脏MMP-2、MMP-9、TGF-β1蛋白表达水平,及MMP-2、MMP-9、TGF-β1 mRNA水平均高于B、C组,差异有统计学意义(P<0.05)。结论研究大肠埃希菌感染致急性肾盂肾炎模型大鼠的肾脏状况及MMP-2、MMP-9、TGF-β1水平随感染天数增加的变化情况,为急性肾盂肾炎治疗方案的提升提供参考。

OBJECTIVE Pyelonephritis rats model established by Escherichia coli infection to was used to observe the kidney status and changes of matrix metalloproteinase-2(MMP-2),matrix metalloproteinase-9(MMP-9),transforming growth factor-β1(TGF)levels.METHODS Acute pyelonephritis model rats were prepared by bladder infusion of E.coli liquid;rats were divided into 5 test groups,including the blank group(B),control group(C),infection for 5 days(M1),infection for 10 days(M2)and infection 15 days(M3)groups.At the end of the test,the health status in the rats of each test group,kidney histological indicators were detected,and the body weight,weight of both kidneys,bladder fluid and kidney colonies,number of inflammatory cells,the expression levels of MMP-2,MMP-9,TGF-β1 protein and mRNA levels of MMP-2,MMP-9 and TGF-β1 were determined.RESULTS The health status and kidney histological indexes in the model rats of the M1,M2,and M3 groups were significantly lower than those in the B and C groups.The rats of M1,M2,and M3 test groups had decreased activity,poor appetite,and less resistance when arrested.The surface of the kidney was pale and scarred,the demarcation line between the skin and the pulp was blurred in the longitudinal section,the renal pelvis and calices were deformed,and the renal pelvis mucosa was infiltrated with inflammatory cells.The body mass,number of bacterial colonies and inflammatory cells in the model group were significantly different between the control group and B and C groups(P<0.05).With the increase of infection days,the number of bacterial colonies and the number of inflammatory cells increased.The protein expression levels of MMP-2,MMP-9,TGF-β1 and the mRNA expression levels of MMP-2,MMP-9 and TGF-β1 in the M1,M2,and M3 test groups were significantly higher than those in the B and C groups(P<0.05).CONCLUSION The changes of MMP-2,MMP-9,TGF-β1 levels in rats with acute pyelonephritis caused by E.coli infection with the increase of infection days may provide a reference for the improvement of the treatment plan of acute pyelonephritis.