中文摘要：

目的研究板蓝根体外刺激人肺腺上皮细胞（SPC—A—1）是否诱导表达具有抗菌活性的人-β-防御素-2（HBD-2）表达，并进一步探讨该表达是否存在浓度和时间依赖性效应，为进一步在动物水平探讨HBD-2的表达与中药之间的量效关系及时效关系提供依据。方法体外培养SPC—A—1细胞，设置板蓝根5个浓度梯度，另设阳性对照和空白对照各1个，分别刺激贴壁生长的SPC—A—1细胞，应用RT-PCR技术检测SPC—A—1细胞HBD-2mRNA的表达情况，获取最佳表达浓度；再以最佳浓度经不同时间点刺激SPC—A—1细胞，得到表达诱导时间和持续时间。结果研究显示板蓝根能够上调（SPC—A—1）细胞HBD-2 mRNA的表达，且这种表达与板蓝根具有浓度和时间依赖性，当浓度为100μg/ml，刺激8h时，HBD-2mRNA的表达达到最高。结论板蓝根可诱导HBD-2基因的表达，当浓度为100μg/ml，刺激8h时，其表达达到最高。

英文摘要：

Objective To identify whether radix isatidis upregulate the expression of human-β-defensin-2（HBD-2）in pulmonary epithelial cells（ SPC-A-1） ;Exploring the optimal stimulating concentration and stimulating time of radix isatidis. Methods Five different concentrations which were 12. 5,25. 0,50. 0,100.0 and 200.0μg/ml of radix isatidis were added to SPC-A- 1, the induction of human-β- defensin-2 was tested. Then SPC-A-1 was stimulated at different time by optimal concentration of radix isatidis, the expression of HBD- 2mRNA in pulmonary epithelial cells was detected by RT-PCR.Results It was found that radix isatidis can upregulate HBD-2mRNA, the optimal concentration was 100μg/ml, the maximal expression of HBD-2mRNA occoued after 8 hours. Conclusion The results suggest that radix isatidis is a inducer of human-defensin-2 in human pulmonary cells, the optimal stimulating concentration was 100.0μg/ ml and optimal sitmulating time was after 8 hours.