【摘要】 目的研究冷空气吸入刺激对哮喘豚鼠血浆及肺组织中神经激肽A(NKA)含量及NKA mRNA表达的影响,并探讨其影响的机制。方法用卵蛋白超声雾化法制作豚鼠哮喘模型;哮喘组15例:按哮喘模型制作要求致敏及诱喘,诱喘后24 h取材。冷空气刺激组15例:致敏及诱喘同哮喘组,于诱喘前5 d、诱喘当天及取材当天(诱喘后24 h),每日吸入冷空气20 min;正常对照组:用生理盐水替代卵蛋白雾化溶液,方法同上。用酶联免疫法检测各组血浆及肺组织中NKA含量;用RT-PCR方法检测肺组织中NKA mRNA的相对含量。结果哮喘组豚鼠血浆、肺组织中NKA含量及肺组织中NKA mRNA的相对含量均明显高于正常组豚鼠, 差异非常显著(均P<0.01);冷空气刺激组哮喘豚鼠,其血浆、肺组织中NKA含量及肺组织中NKA mR-NA的相对含量均明高于哮喘组豚鼠,差异显著(均P<0.05)。结论NKA参与了卵蛋白诱发的豚鼠哮喘发病机制;冷空气吸入刺激能显著增加哮喘豚鼠血浆及肺组织中NKA含量;冷空气吸入刺激具有在转录水平上调NKA mRNA表达的作用,由此导致血浆及肺组织中NKA蛋白含量增多。更多还原

【Abstract】 Objective: To study the changes of neurokinin A (NKA) and NKA mRNA expression in lung tissues of asthmatic guinea pigs stimulated with inhaling cold air and investigate the mechanism. Methods: The model of asthma in guinea pigs were made by exposure to aerosolized ovalbumin.Asthma group:15 animals were sensitized by exposure to aerosolized ovalbumin and challenged with the same antigen; the animals were anatomized after 24 h of the last ovalbumin challenge. Stimulated with inhaling cold air group: 15 animals were sensitized and chanllenge with aerosolized ovalbumin as Asthma group; besides, the animals were inhaled cold air (20 min per day)from the 5 day before challenged to the day for anatomizing(after 24 h of the last ovalbumin challenge). Normal contral group (15 animals): the aerosolized ovalbumin was replaced by NS. The contents of NKA in plasma and lung tissue were detected by ELISA to all groups; Reverse transcription- polymerase chain reaction to detected the NKA mRNA expression in lung tissues to all groups. Results: The levels of NKA in plasma, lung tissue and NKA mRNA expression in lung tissue of asthma group were significantly higher than normal control group( P <0.01, respectively); Stimulated with inhaling cold air group, the levels of NKA in plasma, lung tissue and NKA mRNA expression in lung tissue were significantly higher than asthma group( P <0.05, respectively). Conclusions: NKA takes a part in the pathogenesis of asthma in guinea pigs induced by ovalbumin. Stimulated with inhaling cold air can significantly increase the levels of NKA in plasma and lung tissue of asthmatic guinea pigs, the mechanism is related to that stimulated with inhaling cold air can make the NKA mRNA expression up-regulated in asthmatic lung tissue.更多还原