内皮祖细胞移植对急性肺损伤大鼠肺组织内皮素的影响

Effects of endothelial progenitor cells on endothelin-1 expression in lung injury rats

目的 观察内皮祖细胞（EPCs）移植对损伤肺组织内皮素（ET-1）表达的影响,从而进一步探讨干细胞移植对肺损伤的治疗作用.方法 将清洁级同遗传背景的SD大鼠24只,随机分为假损伤组、肺损伤组和细胞移植组,每组8只.采用密度梯度离心法分离、培养SD大鼠的骨髓EPCs.肺损伤组、细胞移植组大鼠经大鼠尾静脉注射脂多糖5 mg/kg建立肺损伤模型.造模后半小时,肺损伤组、细胞移植组大鼠经尾静脉注入内皮祖细胞悬液0.5 mL ,约2×106 个细胞;假损伤对照组大鼠同法注入等量的PBS溶液0.5 mL .分别于1周后处死动物取肺组织,采用RT-PCR、Western blot方法分析ET-1的表达情况.结果 与假损伤组相比,肺损伤组中的ET-1显著增加,细胞移植组中ET-1表达较肺损伤组显著减少,组间差异有统计学意义（P〈0.05）.结论 内皮祖细胞移植可以下调急性损伤肺组织的ET-1的表达,对急性肺损伤具有治疗作用.

Objective To investigate the effect of endothelial progenitor cells （EPCs） transplantation on endothelin - 1 expression in lung injury. Methods Clean SD rats were randomly divided into three groups with 8 rats in each group. All animals used in this study were of the same genetic background. Lung injury models were created by intravenous injecting lipopolysaccharide of 5 mg/kg into rats of the lung injury group and cell transplantation group. Rat models in a sham injury group only intravenous injecting Sodium Chloride. Half an hour later, rats of the cell transplantation group and sham injury group were injected with 0. 5 mL of EPCs of 2. 0 × 10^6 per rat into the tail vein. phosphate buffered solution （PBS） 0. 5 mL was injected into rats of the lung injury group by the same method. 7 days after transplantation , expressions of ET - 1 in lung tissues of three groups were detected by RT - PCR and Western blot. Results Compared to sham group, endothelin - 1 expression in lung injury group and EPCs transplantation group were simultaneously increased （ P 〈 0. 05 ）. Compared to the lung injury group, EPCs in the cell transplantation group reduced the expression of endothelin - 1 （ P 〈 0. 05 ）. Conclusion Transplantation of EPCs down - regulated endothelin - 1 expression in lung injury,which maybe be one better way to cure acute lung injury.