地塞米松对新生鼠高氧肺损伤的作用机制探讨  

Effect of dexamethasone on injury lung in neonatal rats of hyperoxia.

作　　者：朱翠平[1] 杜江[1] 封志纯[1] 

机构地区：[1]南方医科大学珠江医院儿科,广东广州510282

出　　处：《中国儿童保健杂志》2006年第1期57-59,共3页Chinese Journal of Child Health Care

基　　金：2005年国家自然基金资助(30571967)

摘　　要：【目的】探讨地塞米松在新生鼠高氧肺损伤中的作用及其作用机制，为临床合理用药提供参考。【方法】将3dSD新生鼠随机分为高氧（95％左右氧7d）、高氧＋地塞米松和空气氧组；HE染色观察肺组织形态结构，做辐射状肺泡计数（radical alveoli courlt。RAC）；免疫组化检测TGF-β1表达。【结果】①高氧组可见肺泡壁较薄、结构简单化、肺泡大小不均。有些肺泡融合、体积增加，地塞米松组除具有上述高氧组特征外，肺组织结构明显紊乱。部分肺泡壁及间隔破坏;高氧组（9．50±1.05）和地塞米松组（10．03±3．26）RAC值较正常组（13．00±1．79）减少（P均〈0．05）。②TGF—β1免疫组化阳性细胞主要分布在肺间隔，较厚肺泡壁也有散在分布正常组表达较少。散在分布，偶见靠近支气管部位的集中显色；高氧组阳性细胞明显增多。可见明显集聚，地塞米松组阳性显色也明显多于正常组，但多为散在分布。高氧组、地塞米松组和正常组表达积分分别为1．76±0．66、1．62±0．60和1．28±0．64，两组均高于正常组（P值均〈0．05）。【结论】新生鼠3～10d暴褥于高氧环境（95％），可使肺组织TGF—β1表达明显增高，导致肺泡化停滞，地塞米松可加重这一病理改变。[Objectives] To study effect of dexamethasone on Lung tissue in neonatal rats of hyperoxia and related mechanism. [Methods] A randomized controlled study was designed in Sprague-Dawley neonatal rats of 3 days, including hyperoxia group （exposed to 95% O2 for 7days）, hyperoxia＋dexamethasone and control groups. Histologic analysis of lung and radical alveoli count （RAC） were taken according to the HE staining. To analyse TGF-β1 expression with immunohistochemistry. [Results] （1）The lung tissue of hyperoxia in neonatal rats showed thinner walls of alveoli, simpler alveolar structure, smaller or larger alveoli than the tissue in control, as well as expanded and fused alveoli. The tissue with dexamethasone were more severely, showing some destroyed septa and walls of alveoli, resulting in structure turbulence of pulmonary tissue. RAC of rats was （9.50± 1.05）, （10. 03±3.26） respectively, in hyperoxia group and hyperoxia ＋ dexamethasone group, lower than that of rats in control group（ 13.00 ±1.79）（P〈0.05）. （2）The immune staining cells of TGF-β1 located in septa and walls of thick alveoli. In control group, there were less positive cells scattering in the location above in spite of collecting staining in septa near to bronchia by chance. There were more cells stained, collecting in hyperoxia group than in control group （P〈0.05）, and the staining cells in dexamethasone group were more than those of control group （P〈0.05）. [Conclusion] Neonatal rats exposed to 95% O2 from 3 to 10 days of life may has a increased expression of TGF-β1 and arrest of alveolarization, The lung tissue with dexamethasone which could inhibit TGF-β1 expression, showing more severe lung injury.

关 键 词：高浓度氧 肺损伤 TGF-Β 地塞米松 

分 类 号：Q95-33[生物学—动物学]