支气管哮喘小鼠气道重构模型的构建及评价

Reconstruction and evaluation of airway remodeling model in asthmatic mice

目的:用屋尘螨提取液(DHM)制备支气管哮喘小鼠气道重构模型,并初步探讨其量效和时效关系。方法:90只清洁级雌性BALB/c小鼠随机分为空白对照组、DHM低剂量组,DHM高剂量组3组,每组再分为3、6、9周3个亚组。用不同浓度的DHM皮下和腹腔致敏后,多次滴鼻激发,进行支气管肺泡灌洗液(BALF)炎细胞总数和嗜酸细胞计数,测定BALF中IL-4和血清总IgE;采用医学图像分析软件测定支气管壁厚度和气道面积。结果:DHM低剂量组和高剂量组分别与空白对照组比较:①BALF中IL-4、嗜酸细胞和白细胞总数计数以及血清中总IgE均明显升高(P<0.05)。②标准气道壁厚度(d/Pi)和气道壁面积(WA/Pi)均明显增加(P<0.05)。③镜下直接观察3周时小鼠出现明显急性气道炎症,气道壁结构有轻微改变;9周内随时间增加气道结构发生显著改变。DHM高剂量与低剂量组比较,3周时炎细胞和嗜酸细胞计数显著增加(P<0.05);3、6和9周时IL-4和IgE均显著增加(P<0.05);气道测量各指标差异无显著性。结论:屋尘螨提取液能成功诱导BALB/c小鼠支气管哮喘气道重构;在研究的剂量范围内存着明显的量效关系,9周内随时间延长气道重构越来越显著,存在显著的时效关系。

Objective To build an airway remodeling model of bronchial asthma in mouse with house dust mite extract （DHM）, and to investigate the dose effect and time-effect relationship. Methods Ninety SPF BALB/c mice were randomly divided into control group, low dose DHM group and high dose DHM group. Each group was randomly divided into three subgroups： three week, six-week and nine week groups. The mice was challenged with intranasal drip after sensitized with subcutaneous and peritoneal injection of DHM with differet doses. All mice were underwent pulmonary lavage in 24 h after the last challenge, the total inflammation cell count, eosinophil count in BALF, the IL-4 level and total serum IgE level were detected, and the internal perimeter （Pi）, the wall thickness （d） and wall area （WA） of the bronchi were measured by computer image analytical system. Results In both high dose DHM and low dose DHM groups, the total inflammation cell counts and eosinophil counts, the levels of IL-4 and serum total IgE levels were significantly increased （P〈 0.05）3 the d/Pi and WA/Pi were statistically increased （P〈0.05） compared with control group. The airway inflammation was increased significantly since the third week, and there was incremental change of morphologieal parameters in high dose DHM group during 9 weeks. Compared with low dose DHM group, in high dose DHM group, the total inflammation cell and eosinophil counts were increased in 3 weeks （ P〈0. 05）, the levels of IL-4 and IgE were increased in 3, 6 and 9 weeks （P〈0.05）, while the d/Pi and WA/Pi had no significant change. Conclusion DHM can induce airway remodeling model of bronchial asthma in mouse successfully, and the airway remodeling changes obviously with the prolongation of exposured time, and there is significant dose- and time-effect in the study.