血管内皮生长因子及受体在大鼠衰老肾脏的表达

Expression of VEGF and VEGF Receptors in Aging Kidney of Adult Rats

【目的】研究血管内皮生长因子(VEGF)及其受体(VEGFR)在大鼠衰老肾脏的表达及探讨它们在肾脏衰老中的作用。【方法】取3月龄、12月龄大鼠作为对照组,24月龄大鼠作为观察组各6只,提取其肾脏组织的RNA,应用逆转录聚合酶链反应技术(RT-PCR)检测肾脏组织内VEGFmRNA转录水平,以及应用免疫组化技术检测肾小球VEGF和VEGFR蛋白的表达;应用酶联免疫法检测肾组织培养液的VEGF总含量。【结果】3、12、24月龄的大鼠VEGF总的含量(g/L)分别为126.49±32.29,95.14±49.17,79.21±61.17,P=0.048。3、12、24月龄的大鼠VEGFmRNA表达量(g/L)分别是0.821±0.132,0.713±0.143,0.678±0.126,P=0.012。24月龄组VEGFmRNA和VEGF总含量较3、12月龄两组减少(P<0.05);24月龄大鼠肾小球VEGF和VEGFR-2的表达较3、12月龄两组减弱。【结论】证实了随着增龄大鼠肾组织VEGFmRNA转录水平和VEGF含量减少,肾小球VEGF-VEGFR的表达量也随着增龄而减少。肾小球VEGF-VEGFR系统在肾脏衰老过程中起到重要的作用。

[Objective] To investigate the expression of vascular endothelial growth factor (VEGF) and vascular endothelial growth factor receptors (VEGFR) in aging kidney of adult rats and the role of them in aging. [Methods] To select 3-month (n=6) and 12-month (n=6) rats as control groups, 24-month (n=6) rats as observation group. The RNA of the renal tissue was extracted. Then the level of VEGF mRNA in kidney was determined by reverse transcription polymerase chain reaction (RT-PCR); the expression of VEGF and VEGFR in glomerulus were determined by immunohistochemistry. Total quantity of VEGF in culture fluid of renal tissue was determined by enzyme-linked immunosorbent assay (ELISA). [Results] Total quantity of VEGF in 3-, 12-, and 24-month rats were 126.49±32.29, 95.14±49.17, and 79.21±61.17, respectively (P=0.048). The expression levels of VEGF mRNA in 3-, 12-, and 24-month rats were 0.821±0.132, 0.713±0.143, and 0.678±0.126, respectively (P=0.012). VEGF mRNA and total quantity of VEGF in 24-month rat group were lower than those in 3-month and 12-month rat groups (P< 0.05). VEGF and VEGFR in 24-month rats group were lower than the other two groups. [Conclusion] The level of VEGF mRNA and quantity of VEGF are decreased with age. Expression of VEGF and VEGFR in glomerulus is decreased with age. These suggest VEGF-VEGFR system play an important role in aging progression of kidney.