戒烟对吸烟致敏大鼠气道5-脂氧合酶及其mRNA表达的影响

目的 通过研究戒烟对吸烟致敏大鼠气道5-脂氧合酶（5-LO）及其mRNA表达的影响,探讨吸烟及戒烟对支气管哮喘（简称哮喘）气道炎症的影响,为吸烟哮喘患者戒烟及治疗提供依据.方法 雄性Wistar大鼠40只,随机分为对照组、致敏组、吸烟组及戒烟组,每组10只.后3组应用卵白蛋白（OVA）致敏并长期（8周）吸入激发,制备哮喘模型;在激发第3周开始,将吸烟致敏组及戒烟致敏组大鼠置于自制熏箱内进行被动吸烟,吸烟时间为20周,戒烟时间为10周.采用免疫组织化学及原位杂交法检测各组大鼠气道5-LO蛋白及其mRNA的表达.结果 ①吸烟组气道5-LO蛋白的表达（32.58±2.78）及戒烟组气道5-LO蛋白的表达（26.36±2.34）明显高于致敏组（21.65±2.12）和对照组（15.38±1.68）,差异有统计学意义（P值均＜0.01）;戒烟组较吸烟组表达降低,差异有统计学意义（P＜0.01）;致敏组高于对照组,差异有统计学意义（P＜0.01）.②吸烟组气道5-LO mRNA的表达（34.68±2.90）及戒烟组气道5-LO mRNA的表达（27.16±2.38）均高于致敏组（23.55±2.28）和对照组（15.78±1.72）,差异有统计学意义（P值均＜0.01）;戒烟组较吸烟组表达降低,差异有统计学意义（P＜0.01）;致敏组高于对照组,差异有统计学意义（P ＜0.01）.结论 吸烟可使致敏大鼠气道5-LO及mRNA表达增多,加重气道炎症.戒烟后其表达均有所下降,提示戒烟可减轻气道炎症,是防止哮喘发作的有效措施.

Effects of smoke cessation on expressions of 5-lipoxygenase protein and mRNA in smoking sensitized rats airway

Objective To study the effect of smoking and smoke cessation on airway inflammation of asthma and put forward experimental basis for the treatment of asthma of smoking through researching the effect of smoking on the expressional levels of 5-lipoxygenase protein and mRNA in sensitized rats airway.Methods Forty male Wistar rats were divided randomly into control group,sensitized group,smoking group and smoke cessation group.The rats of latter three groups were sensitized and challenged by ovalbumin to establish the asthmatic model.From the challenged third weeks,the smoking group and smoke cessation group rats were put in the self-made fumigating box to smoke passively.The expressions of 5-lipoxygenase protein and mRNA in airway were defected using immunohistochemistry and hybridization in situ in all rats of three groups.Results ① The expressions of airway 5-lipoxygenase protein of the smoking group （32.58 ± 2.78） and the smoke cessation group （26.36 ± 2.34） were significantly higher than those of the sensitized group （21.65 ± 2.12） and the control group （15.38 ± 1.68,all P 〈0.01）,so did the sensitized group and the control group （P 〈0.01）.②The expression of airway 5-lipoxygenase mRNA of the smoking group （34.68 ± 2.90） and the smoke cessation group （27.16 ± 2.38） were significantly higher than those of the sensitized group （23.55 ± 2.28） and the control group （15.78±1.72,all P 〈0.01）,so did the sensitized group and the control group （P 〈0.01）.Conclusions Smoking can increase the expession level of 5-lipoxygenase protein and mRNA in sensitized rats airway and aggravation airway inflammation.Smoke cessation can relieve airway inflammation and is an effective measure for preventing asthma.