牛磺酸对支气管哮喘大鼠气道张力及12/15-脂氧合酶水平的影响

Effect of taurine on airway tension,expression level of 12/15-lipoxygenase in asthmatic rats

目的探讨牛磺酸对支气管哮喘(简称哮喘)大鼠气道反应性的影响。方法 40只SD大鼠随机分为对照组、哮喘组、牛磺酸干预组、地塞米松治疗组,每组10只;以卵清蛋白致敏、雾化激发,建立慢性哮喘模型。牛磺酸干预组、地塞米松治疗组分别于雾化前半小时给予500mg/kg牛磺酸及地塞米松5mg/kg腹腔注射。末次激发后24h处死大鼠,HE染色观察气道炎症及形态学改变,采用Power Lab张力换能器检测离体气管环对支气管收缩剂、舒张剂的反应,ELISA法检测血清中IL-13的表达,免疫组织化学方法观察肺组织12/15-脂氧合酶的表达。结果哮喘组气道上皮不完整,部分黏膜上皮细胞脱落,黏膜下水肿,黏膜下及管周有大量以淋巴细胞、嗜酸粒细胞为主的炎性细胞浸润;牛磺酸组与地塞米松组病理改变均较轻。牛磺酸组与地塞米松组气道对收缩、舒张剂的反应较哮喘组低,血清中IL-13(P<0.05)及肺组织中12/15-脂氧合酶含量(P<0.05)较哮喘组明显降低。结论牛磺酸能降低卵清蛋白介导的哮喘大鼠气道张力,这一作用可能是通过抑制炎症介质的产生、抑制花生四烯酸代谢,进而减轻炎症反应所致。

Objective To investigate the effect of taurine on bronchial asthma （asthma） rats airway reactivity. Methods Forty SD rats were randomly divided into four groups：control group, asthma group, taurine intervention group and dexamethasone treatment group, ten rats in each group. The rats were sensitized and challenged with ovalbumin （OVA） to establish chronic asthma model. Thirty min before each airway challenge, taurine intervention group and dexamethasone treatment group rats were respectively administered intraperitoneally with TAU 500 mg/kg and DXM 5 mg/kg daily for 5 consecutive weeks. The mice were sacrificed 24 h after last aerosol challenge. The sections were stained with HE to assess the morphology change and airway inflammation. ELISA was used to measure IL-13 levels in serum. The Power Lab tension transducer was used to test the response on isolated trachea strips at the different concentrations of acetylcholine and ipratropium bromide. Immunohistochemistry was used to detect the expression of the 12/15-LO in the left lung. Results Airway epithelium was incomplete, part of the mucosa epithelial cell fell off, the mucosa was edema,and mass inflammatory cells infiltration in asthmatic group. Taurine intervention, similar with dexamethasone treatment,can ameliorate the above mentioned symptoms significantly. Compared with asthma group, the response of isolated trachea strips and the levels of IL-13 （ P 〈0.05） in serum and 12/15-LO （ P〈0.05） in left lung significantly decrease in taurine intervented rats. Compared with dexamethasone treatment group, taurine intervention group have similar effect （ P 〉0.05）. Conclusions Taurine could alleviate OVA-induced asthma,which might through decreasing airway tension, restraining mediators of inflammation,and inhibiting arachidonic acid metabolism in lung tissue.