吸入低氧气体对哮喘缓解期豚鼠嗜酸性粒细胞和CD_4^+T淋巴细胞的影响

Effects of hypoxia inhalation therapy on the number of eosinophil and CD_4^+T-lymphocyte in remission stage in asthmatic guinea pigs

目的 :探讨吸入低氧气体防治哮喘的机制。方法 :采用 10 %卵蛋白致敏和 5次 1%卵蛋白吸入诱发复制哮喘豚鼠模型 ,设立正常组、哮喘组和低氧吸入组 3组。用 (13 0± 0 .5 ) %O2 /N2 低氧气体吸入干预哮喘缓解期豚鼠 ,结束时 3组均作血清皮质醇、支气管肺泡灌洗液 (BALF)中嗜酸性粒细胞 (EOS)计数与低密度EOS(HEOS)百分率和外周血CD4+ T淋巴细胞数量以及气道平滑肌张力的测定。结果 :①正常组和低氧吸入组的血清皮质醇含量均非常显著高于哮喘组 (P <0 0 1)。②低氧吸入组BALF中EOS绝对值及HEOS百分率均数均非常显著低于哮喘组 (P<0 .0 1)。③正常组和低氧吸入组外周血CD4+ T淋巴细胞数量明显低于哮喘组 (P <0 .0 1)。④哮喘组气道平滑肌张力增高。结论 :低氧吸入治疗能使哮喘缓解期豚鼠血清皮质醇升高 ,从而使其BALF中EOS和活化的EOS以及外周血CD4+ T淋巴细胞减少 ,能降低气道平滑肌张力 ,减轻气道高反应性 ,有利于预防哮喘复发。

AIM: To explore the mechanism underlying the therapeutic effects of hypoxia inhalation on asthma. METHODS: Guinea pigs were randomized into the normal group(NG), asthmatic group(AG) and the hypoxia inhalation-treated group(HITG). The model of asthma was established in the latter two groups through sensitization and induction with 10% ovalbumin(OA) and 1% OA, respectively. The animals in HITG were treated with hypoxia inhalation (13.0%±0.5% O 2/N 2 mixed gas). The content of serum cortisol, the number of eosinophils(EOS) and percentage of hypodense eosinophils(HEOS) in bronchoalveolar lavage fluid(BALF),the number of CD 4 +T-lymphocyte in peripheral blood(PB) and the tension of airway muscle were determined. RESULTS: (1)The content of serum cortisol was significantly higher in NG and HITG than in AG( P< 0.01); (2)The number of EOS and percentage of HEOS in BALF was significantly lower in HITG than in AG( P <0.01); (3) The number of CD 4 +T-lymphocyte in PB was significantly higher in AG than in HITG( P< 0.01). CONCLUSION: After treatment with hypoxia inhalation, the content of serum cortisol in asthmatic guinea pigs was significantly increased to result in marked decreased of the number of EOS, the percentage of HEOS in BALF, and the number of CD 4 +T-lymphocyte in PB, thus result in the tension of airway muscle and alleviation of the airway hyperresponsiveness. All these may be beneficial to preventing the relapse of asthma.