低压低氧治疗对哮喘豚鼠的影响

目的:探讨模拟高原防治哮喘的机理。方法:用卵蛋白致敏和诱发复制哮喘动物模型,分为哮喘发作组、缓解组和低压舱治疗组,并设立正常对照组进行以下检测:①放免法测定血浆及支气管灌洗液(BALF)中内皮素(ET)含量及血浆皮质醇水平;②肺组织切片光镜检查。结果:①光镜下哮喘发作组肺组织切片见嗜酸性粒细胞(EOS)浸润明显,缓解组浸润较少,治疗组明显减少;②血浆皮质醇水平发作组、缓解组分别明显高于和低于正常组,治疗组与正常组无明显差异;血浆ET含量哮喘缓解组明显高于其他3组,而BALF中ET含量则为发作组明显高于其他3组,后3组之间无明显差异。结论:低压低氧治疗后,哮喘豚鼠血浆及BALF中内皮素降低而血浆中皮质醇增高,肺组织嗜酸性粒细胞浸润减少,这可能是模拟高原环境防治哮喘的机理之一。

Therapeutic effects of hypobaric hypoxia on asthma in guinea pigs

AIM: To explore the mechanism of the therapeutic effect of hypobaric hypoxia on allergic asthmas guinea pigs. METHODS:After the model of asthma was established with ovalbumin(OA) challenge in OA sensitized guinea pigs, the animals were randomized into the asthmas group(AG), the alleviative group(ALG) and hypobaric hypoxia treated group(HHTG). The levels of plasma cortisol and endothelin(ET), ET in bronchoalveolar lavage fluid(BALF) were determined by radioimmunoassay. The pulmonary pathological changes were observed with optical microscope. RESULTS:(1) Infiltration of eosinophils (EOS) in alveolar septum was found in AG and ALG, while it was reduced in HHTG. (2) The level of plasma cortisol was significantly higher in AG than in normal control group(NCG) ( P< 0.01).But it was significantly lower in ALG than in NCG( P< 0.01), there was no difference in plasma cortisol level between HHTG and NCG. (3) The content of ET in plasma was significantly higher in ALG than that in NCG, AG and HHTG( P< 0.01), and ET level in BALF was significantly higher in AG than that in NCG, ALG and HHTG( P< 0 05),however, no significant difference was found among the latter three groups, respectively. CONCLUSION: After the treatment with hypobaric hypoxia, the ET levels of the plasma and BALF were decreaced and the content of plasma cortisol was increaced, and infiltration of EOS in alveolar septum was decreaced in asthmatic guinea pigs.That may be one of the mechanisms by which hypobavic hypoxia prevents and cures asthma.