LTC4及其合成酶与咳嗽变异性哮喘气道重建的相关性研究

目的研究白三烯C4（LTC4）及其合成酶表达与咳嗽变异性哮喘（CVA）气道重建的相关性,探讨CVA的发病机制,为CVA的早期诊断提供理论依据。方法将40例入选患者分为支气管哮喘组、CVA组各20例,另择20例健康人作为对照组。采用ELISA技术检测静脉血中LTC4的含量;应用RT-PCR检测LTC4合成酶在多形核细胞和淋巴细胞中的表达。选择对照组6例、支气管哮喘组6例、CVA组12例分别进行纤维支气管镜检查,取右中叶支气管组织,进行常规石蜡切片,HE染色,光镜下观察并测量基底膜厚度。结果支气管哮喘组LTC4含量及基底膜厚度显著高于CVA组和对照组,CVA组高于对照组（P〈0.01或〈0.05）。各组基底膜厚度与静脉血LTC4含量之间存在相关性（P〈0.05）。LTC4合成酶在CVA组和支气管哮喘组患者中的表达明显高于对照组（P〈0.05）。LTC4合成酶在多形核细胞中表达相对较强,在淋巴细胞中表达相对较弱。结论 CVA存在气道重建,静脉血中LTC4及其合成酶的表达可以作为CVA的快速诊断的指标之一。

Relationship between expressions of LTC4,LTC4 synthase and airway remodelling in cough variant asthma patients

Objective To study the relationship between the expression of LTC4,LTC4 synthase and airway remodelling in cough variant asthma（CVA）.Methods 20 patients with bronchial asthma,20 patients with CVA and 20 healthy subjects were studied.The blood level of LTC4 was determined by ELISA,the gene expression of LTC4 synthase by RT-PCR.Bronchal biopsy specimens were obtained from 6 healthy subjects,6 bronchial asthmatic and 12 CVA patients,and made with routine paraffin section and HE staining.The basement membrance thickness was measured with light microscopy.Results The LTC4 level of bronchial asthma group was significantly higher than that of CVA group and control group（P〈0.01）.The LTC4 level of CVA group was higher than that of control group（P〈0.05）.The basement membrane thickness significantly associated with the LTC4 level（P〈0.05）.LTC4 synthase expressions in bronchial asthma group and CVA group were higher than that of control group（P〈0.05）.LTC4 synthase expression in polymorphocyte was higher than that in lymphocytes.Conclusions The airway remodeling occurs in CVA.LTC4 and LTC4 synthase gene expression can be used as one of the rapid diagnostic criteria of CVA.