摘要
目的探讨地塞米松对哮喘豚鼠气管平滑肌毒蕈碱受体(MR)mRNA的表达及肺泡灌洗液(BALF)嗜酸性粒细胞(Eos)浸润的影响。方法30只健康豚鼠随机分为3组:正常对照组、哮喘组和地塞米松治疗组。后两组制作成哮喘豚鼠模型,再激发用药。测定BALF的细胞总数及细胞分类,观察肺组织的病理改变,进行气管平滑肌的M2R、M3RmRNART-PCR半定量分析。结果各组BALF的Eos计数,地塞米松治疗组(11.0±3.1)较正常组(2.8±3.0)和哮喘组(29.2±7.3)有显著差异(P<0.01)。地塞米松治疗组肺组织充血水肿明显,但Eos肺组织浸润较哮喘组有明显减少。气管平滑肌的MRmRNART-PCR半定量分析显示,地塞米松治疗组M2R(0.90±0.14)与正常组(0.50±0.16)及哮喘组(1.26±0.24)比较均有显著差异(P<0.01),地塞米松组M3R与哮喘组比较有显著差异(P<0.01),与正常组比较无显著差异;正常组与哮喘组比较,M2R和M3R均有显著差异(P<0.01)。结论哮喘豚鼠M2R表达增加,M3R表达减少;地塞米松治疗可以通过抑制Eos浸润等炎症反应,调节M2R及M3R表达,从而恢复M2R功能,达到治疗哮喘的目的。
Objective To investigate the effect ofdexamethasone on the expression ofmuscarinic receptor （MR） mRNA in smooth muscle and infiltration of eosinophils （Eos） in the airway of asthmatic guinea pigs. Methods Thirty healthy guinea pigs were randomized into 3 equal groups, the control group, asthmatic group and dexamethasone therapy group. Asthma was induced in the latter 2 groups with the asthma-inducing agents and received treatments as indicated. Bronchial alveolar lavage fluid（BALF） were collected subsequently from the guinea pigs for examining the total cell number and cell classification, and histopathologic examination of the lung tissue was performed. Semi-quantitative analysis with reverse transcriptionalpolymerase chain reaction （RT-PCR） was performed for M2 and M3 receptor mRNA in airway smooth muscle. Results Compared with the control and the asthmatic group, the number of Eos in the BALF of dexamethasone therapy group was significantly lower （P〈0.01）. In Spite of the presence ofhyperemia and edema in the lung tissues of the dexamethasone therapy group, Eos infiltration was less severe than that in the asthmatic group. As found by RT-PCR, the quantity of M2 receptor mRNA in the airway smooth muscle of the dexamethasone therapy group was significantly higher than those in both the control and asthmatic groups （P〈0.01）, and the quantity of M3 receptor mRNA in the airway smooth muscle of dexamethasone therapy group was significantly higher than that in the asthmatic group, but did not significantly differ from that in the control group. The quantities of M2 and M3 receptor mRNAs in the control group were both significantly higher than that in asthmatic group （P〈0.01）. Conclusion The expression of M2 receptor is increased in antigenchallenged guinea pigs, and that of M3 receptor decreased..Dexamethasone can treat asthma by inhibiting inflammatory action involving Eos infiltration, regulating the expressions of M2 and M3 receptors and restoring the function of M2 receptor.
出处
《第一军医大学学报》
CSCD
北大核心
2005年第8期986-990,共5页
Journal of First Military Medical University
关键词
地塞米松
哮喘
毒蕈碱受体
嗜酸细胞
dexamethasone
asthma
muscarinic receptor
eosinophils
