地塞米松对哮喘豚鼠肺内脏感觉传入部位TrkA表达的抑制作用

为了探讨地塞米松对哮喘豚鼠肺内脏感觉传入系统(C7T5脊神经节及对应的脊髓后角)TrkA表达的影响,我们利用免疫组织化学和Westernblot方法,研究了哮喘豚鼠C7T5脊神经节及对应的脊髓后角TrkA的免疫反应变化。结果显示:哮喘组豚鼠C7T5脊神经节及对应的脊髓后角TrkA表达明显高于对照组(P<0.01),而地塞米松组则明显低于哮喘组(P<0.01)。结果提示TrkA可能参与哮喘的发病过程,地塞米松抑制哮喘豚鼠TrkA的表达可能是其治疗哮喘的作用机制之一。

THE INHIBITORY EFFECT OF DEXAMETHASONE ON THE EXPRESSION OF TrkA IN THE VISCERAL SENSORY AFFERENT SYSTEM OF THE LUNG ON THE ASTHMATIC GUINEA PIGS

To explore the effect of dexamethasone on the expression of tropomyosin-receptor kinase A TrkA in the visceral sensory afferent system (C_7-T_5 spinal ganglia and the corresponding posterior horn of the spinal cord) of the lung on the asthmatic guinea pigs, the alterations of TrkA immunoreactivity were investigated by means of immunohistochemistry and Western blot. The results show that the expression of TrkA in the C_7-T_5 spinal ganglia and the corresponding posterior horn of the spinal cord of the asthmatic guinea pigs was much higher than that of the control groups (P<0.01). Application of dexamethasone greatly reduced the TrkA expression (P<0.01). The present results indicate that the over-expression of TrkA might be involved in the pathogenesis of the bronchial asthma, and inhibition of its expression by dexamethasone may be one of the mechanisms in the treatment of asthma.