中文摘要：

目的研究肿瘤坏死因子α（TNF-α）对体外培养人牙囊细胞血管内皮生长因子（vEGF）表达的影响。方法原代培养人牙囊细胞，传代至第4代，采用反转录聚合酶链反应（RT—PCR）及酶联免疫吸附试验（ELISA）分别检测TNF—α对体外培养人牙囊细胞VEGF mRNA表达及上清液中VEGF含量改变的浓度和时间效应。结果①不同浓度TNF—α作用1h后，TNF—α处理组人牙囊细胞VEGF mRNA表达均较对照组增强（P〈0．05），最佳效应浓度为25ng／ml；不同浓度TNF—α作用12h后，除1ng／ml组外，其余各组上清液中VEGF蛋白含量明显高于对照组（P〈0．05）。②在时间效应上，25ng／ml TNF—α作用1h后人牙囊细胞VEGF mRNA表达最强，然后随时间延长其表达逐渐下降，但仍强于对照组（P〈0．05）；细胞培养上清液中VEGF蛋白含量随时间延长逐渐增加，但TNF—α处理组VEGF蛋白含量高于对照组（P〈0．05）。结论TNF—α能够促进体外培养人牙囊细胞合成并分泌VEGF。

英文摘要：

Objective To study the effect of tumor necrosis factor-alpha （TNF-α）on the expression of vascular endothelial growth factor （VEGF） in cultured human dental follicle cells. Methods Primary culture of human dental follicle cells was established and the fourth passage cells were used in this study. Concentration-dependent and time-course effects of TNF-α on VEGF mRNA and VEGF protein secretion were determined by reverse transcription-polymerase chain reaction （RT-PCR） and enzyme linked immunosorbant assay（ELISA） respectively. Results （1）In the concentration-dependent study, VEGF mRNA expression was increased after 1 h exposure to various concentrations of TNF-α, compared with the control group（ P 〈 0.05）, and the optimal concentration was 25 ng/ml. VEGF protein secretion was significantly increased after 12h exposure to various concentrations of TNF-α except TNF-α at 1 ng/ml, compared with the control group （ P 〈 0.05）. （2）In the time-course study, using 25 ng/ml TNF-α, 1 h of incubation caused maximal expression of VEGF mRNA. The amount of VEGF mRNA decreased gradually after 3 or more hours of incubation, as compared with 1-h treatment, but it was still greater than the control level（ P 〈 0.05）. VEGF protein secretion was time-dependently increased, but VEGF protein levels in TNF-α treatment groups were significantly higher than those in the control group （P 〈 0.05）. Conclusion TNF-α can up-regulate the expression of VEGF in cultured human dental follicle cells.