高血压大鼠肾脏基质金属蛋白酶及组织型基质金属蛋白酶抑制剂表达与活性的变化

Changes of expression and activity of renal matrix metalloproteinases and tissue inhibitors of matrix metalloproteinases in the stroke-prone spontaneously hypertensive rats

【目的】研究在卒中易感型自发性高血压大鼠(stroke-prone spontaneously hypertensiverat,SHR-SP)肾脏中,基质金属蛋白酶(Matrixmetalloproteinases,MMPs)-2,-9以及组织型基质金属蛋白酶抑制剂(tissue inhibitors of matrix metalloproteinases,TIMPs)-1,-2的表达与活性的变化。【方法】分别采用40只7周龄雄性SHR-SP大鼠及10只同周龄雄性Wistar-Kyoto大鼠作为高血压组与阴性对照组。观察期间定期测量各组大鼠无创鼠尾压。6个月后,处死存活大鼠留取血液及肾脏标本,测定血清肌酐及尿素氮浓度,采用组织病理染色观察两组大鼠肾脏组织学改变,采用明胶酶谱法分析存活大鼠肾脏MMP-2和MMP-9蛋白活性,并采用逆明胶酶谱法及蛋白质印迹分析TIMP-1和TIMP-2蛋白表达和活性。【结果】(1)明胶酶谱分析显示:SHR-SP肾脏中MMP-2活性较WKY组明显增高([3.28±1.17)vs.(1.26±0.62);P<0.01]。(2)逆明胶酶谱分析显示:高血压大鼠肾脏TIMP-2的活性明显高于WKY组([1.12±0.43)vs.(0.78±0.34),P<0.05]。(3)蛋白质印迹结果显示:高血压组大鼠肾脏TIMP-1、TIMP-2表达较对照组高([TIMP-1:(3.44±0.13)vs.(2.31±0.15),TIMP-2:(6.44±0.49)vs(.4.94±0.68),P<0.01]。【结论】SHR-SP肾脏组织中MMP-2及TIMP-2的活性增高,TIMP-1及TIMP-2的表达均明显升高。

[Objective] To investigate the expression and the activity of renal matrix metalloproteinases and the tissue inhibitors of matrix metalloproteinases in stroke-prone spontaneously hypertensive rats （SHR-SPs）. [Methods] 40 male SHR-SPs of 7 weeks old were used as vehicle group and 10 male Wistar-Kyoto rats （WKY） at the same age were used as controls. Throughout the intervention, indirect tail-cuff systolic blood pressure was continuously measured. The survival rats were executed 6 months later. After the blood was collected to measure the plasma creatinine and urea nitrogen, some kidneytissues were embedded for pathological analysis. The activity of MMP-2 and MMP-9 were detected by gelatin zymography, The expression and the activity of tissue inhibitors of matrix metalloproteinase were detected by western blot and reverse zymography. [ Results] （1） Analysis of the activity of MMPs in kidney by zymography demonstrated that the activity of MMP-2 was markedly increased as compared with control group[（3.28 ± 1.17） vs. （ 1.26 ± 0.62）; P 〈 0.01]. （2） The result of reverse zymography demonstrated that the activity of TIMP-2 was also increased in SHR-SPs[（ 1.12 ± 0.43 ） vs. （0.78 ± 0.34）, P 〈 0.05]. （3） Analysis of the expression of TIMPs in kidney by western blot demonstrated that the expression of TIMP-1 and TIMP-2 in SHR-SPs group was markedly increased as compared with controls [（TIMP-I： （3.44 ± 0.13） vs. （2.31 ± 0.15）, TIMP-2：（6.44 ± 0.49） vs. （4.94 ± 0.68）, P 〈 0.01]. [Conclusion]The results of present study showed that the activity of MMP-2, TIMP-2 and the expression of TIMP-1,-2 in the kidney of SHR-SPs were markedly increased.