早期糖皮质激素应用对豚鼠哮喘模型气道重塑影响的病理学研究

Effect of glucocorticoid on airway remodeling of bronchial asthma model of guinea -pigs: a pathologic study

目的探讨慢性哮喘气道重塑的发生及早期应用糖皮质激素对哮喘气道重塑的影响。方法选健康豚鼠60只,随机分成6组:正常组1、哮喘组1、地塞米松治疗组1和正常组2、哮喘组2、地塞米松治疗组2,分别代表急性和慢性模型;用卵蛋白致敏和诱喘,急性模型2周后取支气管肺组织制作病理切片和电镜切片;慢性模型4周后取支气管肺组织制作病理切片和电镜切片。采用计分法对气道病理指标进行评价。结果光镜下急性哮喘模型可见支气管、细支气管上皮细胞脱落、管壁炎症细胞浸润、杯细胞增生、平滑肌增厚,肺泡间隔亦可见炎症细胞浸润。与急性模型比较,慢性哮喘模型基底膜和平滑肌层增厚更明显,支气管壁内可见纤维组织增生。地塞米松治疗后气道炎症细胞浸润减少,基底膜和平滑肌增生减轻。电镜观察显示慢性哮喘模型基底膜层大量成纤维细胞增生、胶原纤维沉积、平滑肌细胞增多肥大。病理指标评分结果示急性哮喘模型EOS浸润、杯细胞增生、基底膜增厚、平滑肌增生、炎症细胞浸润5项指标计分均高于正常组(P<0.05)。慢性哮喘模型EOS浸润、炎症细胞浸润、基底膜增厚、平滑肌增生、管壁纤维化5项指标评分高于正常组,地塞米松治疗后平滑肌增生计分略仍高于正常。慢性哮喘模型与急性哮喘模型比较仅平滑肌增生和管壁纤维化计分有差异(P<0.05)。结论豚鼠哮喘模型存在气道重塑病理改变,慢性模型比急性模型更明显;急性模型的病理变化说明气道重塑在哮喘的早期即开始;糖皮质激素早期应用可预防气道重塑的发展。

[Objective] To explore the airway remodeling in bronchial asthma and the effect of glucooorticoid on airway remodeling in early period of asthma. [Methods] 60 guniea-pigs were divided into six groups： control group 1, asthma group 1, dexmethasone-treated groupl, control group 2, asthma group 2, dexmethasone-treated group 2. The lung were underwent pathologic study after 2 weeks and 4 weeks. [Results] Bronchial epithelial desquamation, inflammation cells infiltration, hyperplasia of goblet cells and smooth muscle cells were seen in acute asthmatic models under optical microscope, the hypertrophy of subepithelial membrane and airway smooth muscle were more distinct in chronic asthmatic models than acute asthmatic models, the hyperplasia of fibroblasts and smooth muscle cells and deposition of collagen in basement can be seen under electron-microscope. The grade of EOS and inflammation cells infilatration, hyperplasia of goblet cell, incrassation of basement membrane, hypertrophy of airway smooth muscle were higher in acute asthmatic group than control group. The grade of EOS and inflammation cells infilatration, incrassation of basement membrane, hypertrophy of airway smooth muscle, airway fibrosis were higher in chronic asthmatic group than control group; The grade of hypertrophy of airway smooth muscle is higher in chronic asthmatic groud than control group.Between chronic asthmatic group and acute asthmatic group,only grade of hypertrophy of airway smooth muscle and airway fibrosis is different（P〈0.05）.[Conclusions]Airway recodeling in chronic asthmatic group is more distinet than acute asthmatic group,which airway remodeling occur in acute asthmatic models suggest that airway remodeling begin from early stage of asthma,the airway remodeling can be inhibitied by glucocorticoid.