中文摘要：

目的：通过上调和沉默1-磷酸鞘氨醇2型受体（S1P2）的表达,探讨其对体外培养的脐静脉内皮细胞的功能影响。方法：采用转染外源S1P2受体质粒上调年轻脐静脉内皮细胞S1P2受体表达;应用RT-PCR和Western印迹检测空白对照组、空载体组和过表达组细胞的S1P2受体表达;同时采用Matrigel胶种植法,观察3组脐静脉内皮细胞的体外管状样结构生成能力;划痕实验分析内皮细胞的损伤愈合能力;迁移实验分析内皮细胞的化学趋化能力。以及通过RNA干扰沉默衰老脐静脉内皮细胞S1P2受体的表达,观察细胞的功能改变。结果：上调年轻脐静脉内皮细胞S1P2受体表达后,过表达组内皮细胞的成管能力、损伤愈合能力和细胞迁移率均明显低于空白对照组和空载体组（P〈0.05）。RNA干扰沉默衰老脐静脉内皮细胞S1P2受体后,干扰组内皮细胞的管状样结构生成能力、损伤愈合能力和趋化能力均明显恢复,显著高于衰老内皮细胞组和干扰对照组（P〈0.05）。结论：S1P2受体调控体外衰老内皮细胞的趋化、形态发生和损伤愈合反应的功能变化。

英文摘要：

Objective： To investigate the variation of senescent endothelial function by regulating the sphingosine-1-phosphate receptor type 2（S1P2） expression in cultured human umbilical vein endothelial cells（HUVECs）.Methods： The S1P2 receptor expression was regulated by transfecting the cDNA or shRNA of S1P2 in cultured HUVECs.The expression levels of S1P2 receptor in HUVECs were detected by RT-PCR and Western blot.EC chemotaxis was measured by the transwell migration assay.The wound healing assay was performed by a scratch wound model on EC monolayer.Matrigel morphogenesis assay was employed to assess the in vitro angiogenic responses.Results： After up-regulating the S1P2 expression in young ECs,the S1P-stimulated formation of a tubular-like network in Matrigel was dramatically diminished in transfected ECs（P﹤0.05）.Quantification of the wound healing assay showed that transfected ECs grew much slower than young ECs（P﹤0.05）.The chemotactic capability was significantly decreased in transfected ECs（P﹤0.05）.Furthermore,the senescent-associated impairments were revoked by the downregulation of S1P2 receptor in senescent HUVECs.Conclusion： The impaired functions（chemotactic,wound-healing and morphogenetic responses） in senescent HUVECs in vitro are mediated by S1P2 receptor.