凝血酶受体在衰老大鼠肾组织中的表达变化特点

Changes in activation of thrombin receptor in renal tissues of senile rats

目的检测衰老大鼠肾小球凝血酶受体与纤维蛋白的表达变化,明确凝血酶受体活化的意义。方法选用3月、12月与24月龄Wistar大鼠,采用改良的Lendrum纤维蛋白染色法与免疫荧光法检测纤维蛋白的沉积,免疫组化方法检测肾小球凝血酶受体PAR-1与转化生长因子β(TGF-β)在肾组织中的表达。半定量PCR法检测PAR-1mRNA的表达。结果3月、12月与24月龄大鼠肾小球内均未检测到纤维蛋白的表达。PAR-1在3月龄鼠肾小球内皮、系膜与上皮细胞中广泛表达;24月龄鼠肾小球内PAR-1的表达明显减少。PAR-1mRNA和肾小球TGF-β的表达随增龄明显增加。结论衰老大鼠肾小球凝血酶的活化不伴有纤维蛋白的形成,活化的凝血酶受体可能在衰老相关肾脏结构变化中发挥重要作用。

Objective To determine the changes in expressions of thrombin receptor and fibrin deposit in glomeruli during the process of senility. Method Rats were divided into 3 groups （8 rats in each group） ： 3-month-old group （3m）, 12-month-old group （12m） and 24- month-old group （24m）. Fibrin deposition was detected by Martius-Scarlet-Blue staining and direct imrnunofluorecence method. Imrnunohistochemical studies were performed to detect the expression of thrombin receptor （PAR-1） and transforming growth factor-β （TGF-β）. Semi-quantitatlve PCR was performed to detect the changes in PAR-1 mRNA expression. A quantitative analysis of the expressions was performed by image analysis system. Result Significant pathological changes were found in glomeruli during the process of senility. Fibrin deposition was not observed in glomeruli in different groups. Significant expression of PAR-1 was found in glomerular endothelial cells, mesangial cells and epithelial cells in 3m rats. On the contrary, in 24m rats, PAR-1 expression in glomeruli was significantly decreased. Expression of TGF-β was increased with senility in glomeruli. PAR-1 gene expression, barely detectable in control tissue, was strikingly increased in 24m rats. Conclusion Thrombin receptor activation could be found in glomeruli of senile rat, and it is independent of fibrin deposition, Activation of PAR-1 may play an important role in the process of renal senility.