血管内皮生长因子联合地塞米松对胎鼠肺泡Ⅱ型细胞的影响

Effects of Vascular Endothelial Growth Factor Combined with Dexamethasone on Development of Alveolar Epithelial Cells Type II(ACEⅡ)

目的研究联合使用血管内皮生长因子(VEGF)和地塞米松对胎鼠肺泡Ⅱ型细胞发育和肺泡表面活性物质结合蛋白B(SP-B)表达的影响,为防治早产儿呼吸窘迫综合征寻找新途径。方法取孕20 d的W istar大鼠剖腹取胎鼠,原代培养肺泡Ⅱ型细胞,将所得肺泡Ⅱ型细胞分成4组,分别加入VEGF、地塞米松、VEGF+地塞米松、空白培养液(即对照组),孵育后测定各组胎鼠肺泡Ⅱ型细胞VEGF及其受体F lt-1、F lk-1和SP-B。结果VEGF组、地塞米松组与VEGF+地塞米松组SP-B均阳性表达,对照组SP-B阴性表达;VEGF组与VEGF+地塞米松组VEGF、F lt-1、F lk-1阳性表达,地塞米松组VEGF、F lt-1、F lk-1阴性表达。结论VEGF能促进肺泡发育和肺表面活性物质SP-B的合成与分泌,拮抗地塞米松下调肺泡Ⅱ型细胞受体表达的作用。

Objective To study t-he effects of vascular endothelial growth factor （VEGF） combined with dexamethasone on expression of pulmonary surfactant protein B so as to explore a new route to prevent and cure respiratory distress syndrome （RDS） in premature infants. Methods Rat embryos were got from Wistar rats at 20 days gestation period. Primary cuhure of AEC Ⅱ was done. The experiment was divided into VEGF group, dexamethasone group, VEGF plus Dexamethasone group and control group to determine the amount of VEGF with its receptors Flt-1 and Flk-1 and expression of pulmonary surfactant protein B by immunology histochemistry. Results SP-B showed prositive expression in VEGF group, dexamethasone group and VEGF plus dexamethasone group. Control group showed negative expression of SP-B. VEGF group and VEGF plus dexamethasone group showed positive expression of VEGF, Flt-1 and Flk-1. Dexamethasone group showed negative expression of VEGF, Flt-1 and Flk-l. Conclusion VEGF can promote the synthesis and secretion of pulmonary surfactant protein B and antagonise the underregulation of AEC Ⅱ receptors expression by dexamethasone. VEGF and dexamethasone can improve the function of pulmonary epithelial ＇ceils through promoting the expression of pulmonary suffactant protein B.