布地奈德对哮喘大鼠气道重塑和平滑肌肌动蛋白-α表达的影响

The Effects of Budesonide on Airway Remodelling and Expression of SMA-α in Asthmatic Rats

目的 :探讨哮喘大鼠气道平滑肌肌动蛋白 α(SMA α)表达与气道重塑的关系 ,评价布地奈德治疗对两者的影响。方法 :SD大鼠分为正常对照组 (A组 ,n =8)、哮喘模型组 (B组 ,n =8)和哮喘模型布地奈德驱动雾化吸入治疗组 (C组 ,n =8) ;采用二步法免疫组化技术和计算机图象分析系统对大鼠气道SMA α表达和气道重塑进行研究。结果 :①与A组比较 ,B组大鼠气道平滑肌 (ASM )厚度和上皮厚度均显著增加 (P <0 .0 0 1) ,而气道直径显著减小 (P <0 .0 0 1) ;②与B组比较 ,C组大鼠平滑肌厚度和上皮厚度均显著下降 (P <0 .0 0 1) ,而气道直径显著增大(P <0 .0 0 1) ;③与A组比较 ,B组大鼠气道SMA α表达水平显著升高 (P <0 .0 0 1) ,C组亦升高 (P <0 .0 5 ) ;与B组比较 ,C组大鼠气道SMA α表达水平显著下降 (P <0 .0 5 ) ;结论 :气道SMA α表达水平的上调可能是导致气道重塑反应发生的机制之一 ,布地奈德治疗可延缓该反应的发生。

Objective: To study the relationship between the airway remodeling and expression of airway smooth muscle actin-α(SMA-α) in asthmatic rats, and to evaluate the effects of budesonide on them.Method: The experimental sprague dawley (SD) rats were divided into three groups: the control group (Group A,n=8), asthmatic model group (Group B,n=8) and budesonide inhalation group (Group C,n=8). The method of two-step immunohistochemistry and techniques of computer-assisted image analysis were used to detect the changes of the airway remodelling and the expression of SMA-α.Result: ① Compared with those in Group A, the thickness of the epithelia and the airway smooth muscle (ASM) in Group B were significantly increased (P<a(c)0.001aa￡(c)while the airway diameter was notably decreased(P<a(c)0.001aa￡(c). Compared with the thickness of the epithelia and the ASM in Group B, those in Group C were significantly decreased (P<a(c)0.001aa￡(c), while the airway diameter was notably increased (P<a(c)0.001aa￡(c). ② Compared with that in Group A, the expression level of SMA-α in Group B had a great increase (P<a(c)0.001aa￡(c), so did it in Group C (P<a(c)0.05aa￡(c). There was a great decrease of SMA-α level in Group C, compared with Group B(P<a(c)0.05aa￡(c).Conclusion: The enhancement of the expression level of airway SMA-α may be one of the mechanisms contributing to the airway remodeling, and with the treatment of budesonide, the course of the airway remodeling can be delayed.