血管钙化大鼠肾动脉BMP2/Smad1/Runx2信号通路的表达

Expression of BMP2/Smad1/Runx2 Signal Pathway in Renal Artery of Rat with Vascular Calcification

目的观察血管钙化大鼠模型肾动脉上骨形态蛋白2(BMP2)/Smad1/Runt相关转录因子2(Runx2)信号通路的表达及其变化规律,探讨BMP2/Smad1/Runx2信号通路激活在肾动脉钙化中的作用。方法将24只雄性SD大鼠随机分为对照组和钙化组,钙化组建立维生素D3和尼古丁诱导的大鼠血管钙化模型,对照组给予生理盐水和花生油。6周后采用Von Kossa染色检测肾动脉钙化程度,钙离子试剂盒测定大鼠肾动脉钙含量,实时荧光定量PCR检测肾动脉组织中BMP2、Smad1、Runx2mRNA水平,免疫组化法观察BMP2、Smad1、Runx2及α-平滑肌肌动蛋白(α-SMA)的表达。结果 Von Kossa染色见钙化组大鼠肾动脉有大量黑色颗粒沉淀。钙化组血管钙含量高于对照组(P<0.05)。与对照组相比,钙化组大鼠肾动脉组织BMP2、Smad1、Runx2 mRNA的水平升高(P<0.05),BMP2/Smad1/Runx2信号通路蛋白在肾动脉的表达亦同步上调,而α-SMA的表达较对照组下降(P<0.05)。相关分析表明,大鼠肾血管钙含量与肾动脉组织BMP2mRNA(r=0.655,P<0.05)、Smad1mRNA(r=0.735,P<0.05)、Runx2mRNA(r=0.734,P<0.05)均呈正相关。结论 BMP2/Smad1/Runx2通路的表达变化与肾动脉钙化的严重程度相关,提示BMP2/Smad1/Runx2信号通路参与了肾动脉钙化的发生发展。

Objective To investigate the activation and its role of bone morphogenetic protein 2（BMP2）/Smad1/Runt-related transcription factor 2（Runx2）signal pathway in renal artery of rat models with vascular calcification.Methods Twenty four male SD rats were randomly divided into control group and calcification group.Rat vascular calcification model was constructed by administration of vitamin D3 plus nicotine.Vascular calcification was confirmed by Von Kossa staining and calcium content was detected by calcium assay.Real time-PCR was applied to detect the expression of BMP2,Smad1,Runx2 mRNA,and immunohistochemistry was used to measure the protein levels of BMP2,Smad1,Runx2,α-smooth muscle actin（α-SMA）.Results Von Kossa staining showed a large number of black granules deposited in renal artery.Calcium content in calcification group was significantly higher than that in normal group.Compared with the control group,the expressions of BMP2,Smad1 and Runx2mRNA in renal artery were increased in calcification group.The protein levels of BMP2,Smad1 and Runx2were higher while the expression ofα-SMA was lower in calcification group than those in control group.The correlation analysis was found a positivie correlation between the calcium content and BMP2 mRNA（r=0.655,P0.05）,Smad1mRNA（r=0.735,P0.05）,Runx2 mRNA（r=0.734,P0.05）.Conclusion The expression of BMP2/Smad1/Runx2 signal pathway was strongly correlated with the severity of vascular calcification,which may be involved in the occurrence and development of vascular calcification.