支气管肺发育不良新生兔肺组织中转化生长因子β1的表达

Expression of TGF-β_1 in lung tissue of new-born rabbits with bronchopulmonary dysplasia

目的:探讨高浓度氧并机械通气致新生兔支气管肺发育不良(BPD)中肺组织转化生长因子β1(TGF-β1)mRNA及蛋白表达的变化。方法:120只新生兔随机分为4组,每组30只。A组给予高吸气峰压(2.45kPa)机械通气,B组给予中吸气峰压(1.77kPa)机械通气,C组给予低吸气峰压(0.98kPa)机械通气,机械通气中均吸入高浓度氧(体积分数90%)。A、B、C组各分为3个亚组,每个亚组10只,通气时间分别为1h、3h、6h,正常对照组(D组)不做任何处理。通气结束,颈动脉放血处死动物。分别应用RT-PCR及免疫组织化学方法测定肺组织TGF-β1 mRNA及蛋白的表达。结果:高浓度氧并机械通气处理后,TGF-β1蛋白表达3h增加,6h达高峰,肺组织TGF-β1 mRNA 1h增加,3 h达高峰,A组增加较B组、C组明显,均高于D组(P<0.05)。结论:高浓度氧并机械通气诱发的BPD中存在TGF-β1的过度表达,其机制可能与抑制肺泡的发育成熟有关。

Aim： To explore the expression and significance of transforming growth factor-β1 （TGF-β1 ） in new-born rabbits with hyperoxia and ventilation-induced bronchopulmonary dysplasia（BPD）. Methods： Sixty newborn rabbits were randomly diVided into four groups： with 90% O2 and mechanical Ventilation（ MV）, grOup A received high peak inspiratory pressure, group B received moderate peak inspiratory pressure,group C received low peak inspiratory pressure, and group D received no mechanical ventilation with room air. The expression of TGF-β1 mRNA and protein was measured by immuno histochemical methods and RT-PCR after 1 h.3 h.6 h ventilation. Results： The expression of TGF-β1 mRNA in the group A,B, and C increased at 1 h and reached peak at 3 h.and the expression of TGF-β1 protein increased at 3 h and reached peak at 6 h. Compared with group B and group C ,the expression of TGF-β1 mRNA and protein in group A increased obviously. The expression of TGF-β1 mRNA and protein in group A,B, and C was higher than those in group D. Conclusion： The overexpression of TGF-β1 might play an important role in hyperoxia and ventilation-induced BPD. which may be caused by pulmonary alveoli dysplasia.