吸入糖皮质激素对哮喘内皮素和内皮素转化酶mRNA表达的影响

Effect of inhaled corticosteroids on the mRNA expressions of endothelin 1 and endothelin converting enzyme in bronchial asthma

目的探讨内皮素１（ＥＴ－１）和内皮素转化酶（ＥＣＥ）ｍＲＮＡ在哮喘气道粘膜的表达，以及吸入激素对其表达的影响。方法应用逆转录－ＤＮＡ聚合酶链反应，测定支气管粘膜组织ＥＴ－１和ＥＣＥｍＲＮＡ的表达量；对支气管粘膜炎症程度进行评分。结果哮喘非激素组（１０例）和对照组（１０名）ＥＴ－１ｍＲＮＡ表达量分别为０．８６±０．０６，０．１４±０．０６（Ｐ＜０．０５）；ＥＣＥｍＲＮＡ表达量分别为０．３１±０．０４，０．３０±０．０５（Ｐ＝０．２３８）；哮喘激素组（１０例）ＥＴ－１ｍＲＮＡ表达量为０．２２±０．０１，ＥＣＥｍＲＮＡ表达量为０．１６±０．０１；哮喘非激素组粘膜炎症评分为６．０±１．９，且与ＥＴ－１ｍＲＮＡ表达量呈正相关（ｒ＝０．７８，Ｐ＜０．０５）。结论哮喘支气管粘膜ＥＴ－１ｍＲＮＡ表达增高明显，而ＥＣＥｍＲＮＡ无明显改变；吸入糖皮质激素显著抑制ＥＴ－１和ＥＣＥｍＲＮＡ的表达。

Objective To investigate the expressions of endothelin 1(ET 1) and endothelin converting enzyme (ECE) mRNA in bronchial mucosal biopsis from asthmatics, and the effect of inhaled corticosteroids on the expressions of ET 1 and ECE genes. Method The expressions of ET 1 and ECEmRNA in bronchial mucosal tissue were evaluated by reverse transription DNA polymerase chain reaction (RT PCR); With fibro bronchoscopy, the naked eye inflammatory severity and inflammatory score of bronchial mucosas were recorded. Result (1) The expression level of ET 1 mRNA was 0.86±0.06 in non steroids treated group and 0.14±0.06 in control non asthmatic group. The expression of ECE mRNA in non steroid group was 0.31±0.04, and 0.30±0.05 in control group, P =0.238. (2) The ET 1 and ECE mRNA expressions were 0.22±0.01 and 0.16± 0.01 respectively in steroid treated group. (3) The naked eye bronchial mucosal inflammatory score was 6.0±1.9 in non steroids treated group, moreover, the expression of ET 1 mRNA was positively correlated with the score ( r = 0.78, P <0.05). Conclusion There was markedly higher ET 1 mRNA expression in the bronchial mucosa in asthmatics, but the ECE mRNA expression was unchanged significantly; Inhaled corticosteroids obviously inhibited both ET 1 mRNA and ECE mRNA expressions in bronchial mucosa, which may be one of the anti inflammatory mechanism of inhaled corticosteroid in management of bronchial asthma.