哮喘豚鼠肺内P物质的分布与地塞米松对其影响

The distribution of substance P in the lungs of asthmatic guinea pigs and the influence of dexamethasone on the distribution

目的研究哮喘豚鼠肺内Ｐ物质（ＳＰ）的分布及地塞米松对其影响。方法实验动物分为３组即哮喘组、地塞米松组和对照组。采用兔抗ＳＰ血清、免疫组织化学ＡＢＣ法和葡萄糖氧化酶－ＤＡＢ－镍呈色及计算机图像分析技术进行测定。结果与对照组相比，哮喘豚鼠肺内支气管至终末细支气管有较密集的ＳＰ免疫反应（ＳＰ－ＩＲ）阳性串珠状纤维分布，成束走行，以平滑肌层和基底膜为主。此外，呼吸性细支气管和肺泡管也可见阳性纤维。地塞米松处理后，ＳＰ－ＩＲ阳性纤维的分布和形态与对照组基本类似。结论气道变应性炎症引起ＳＰ－ＩＲ阳性纤维增生可能是哮喘发作时体液ＳＰ增多的主要原因之一。

Objective To investigate the distribution of substance P(SP) in the lungs of asthmatic guinea pigs and the effects of dexamethasone on its distribution. Methods Guinea pigs were divided into 3 groups: asthma group, dexamethasone treated group and control group. Rabbit serum against SP, immunohistochemical ABC method and glucose DAB nickel technique for staining and computer image analysis were used in this study. Results There was distribution of SP IR positive fibres in airways in asthma group than the other two groups. The positive fibres, emerged like a string of beads, were present as large fibre bundles in the smooth muscle layer and basement membrane. Additionally, in the asthma group SP IR positive fibres were detected on the walls of respiratory bronchioles and alveolar ducts in contrast to the other groups. There was no differance in distribution and morphorlogical characteristic between the control group and the dexamethasone treated group. Conclusion Repeated antigen challenges, which cause the allergic inflammation of airways, may result in the growth of SP containg nerve fibres in the airway and synthesis of SP in neurons. These may be involved in the persistence and exacerbation of airway inflammation in asthma. Dexamathasone can reverse the distribution of SP IR positive fibres to the normal status in airway walls of asthma guinea pigs.