【作者】 黄艳；

【导师】 李俊； 金涌；

【作者基本信息】 安徽医科大学 ， 药理学， 2005， 硕士

【摘要】 慢性支气管炎（慢支）是严重危害人类健康的常见病、多发病。目前认为,大气污染、吸烟、病原体感染及过敏因素等与慢性支气管炎的发病密切相关,但发病后的机体免疫功能状态直接和（或）间接影响慢性支气管炎的发生和发展。因此,纠正或调节机体免疫功能紊乱可能是防治慢性支气管炎的重要手段之一。 目前对慢性支气管炎的治疗主要着眼于抗炎、镇咳、平喘作用的研究,至今尚无令人十分满意的药物。而对于改善机体免疫功能状态的免疫调节药物,尤其是具有免疫调节作用的中药的研究还没有引起足够的重视。鉴于慢性支气管炎免疫功能紊乱的病理机制和枇杷叶三萜酸（Triterpene acids of Loquat.Leaf,TAL）高效、低毒的作用特征,本实验室前期研究了TAL的抗炎及免疫调节作用;观察其镇咳、祛痰和平喘作用;同时采用正交设计实验方案,联合应用BCG和LPS构建了大鼠慢性支气管炎模型,探讨了TAL对慢性支气管炎的治疗作用。本课题旨在前期研究的基础上,主要以肺泡巨噬细胞（AM）为研究靶点,进一步探讨TAL对慢性支气管炎治疗作用的分子机制,为将其开发为治疗慢支的新药提供试验依据。主要研究内容如下: 1.大鼠慢性支气管炎（CB）模型的制备 在参照气管内注入脂多糖（LPS）方法的基础上,联用卡介苗（BCG）作为佐剂,采用正交试验设计方案制备大鼠CB模型。结果显示:尾静脉注射BCG(5mg·kg^-1)和气管内注入LPS 200μL（1g/L）联合应用,饲养3周后可出现慢性支气管炎的典型病理形态学改变,提示该方法是用于研究慢性支气管炎发生及发展机制的简便可靠的模型。 2.AM的鉴定及TAL对CB大鼠AM形态及活性的影响更多还原

【Abstract】 The anti-inflammatory mechanisms of Triterpene Acids of Loquat.Leaf (TAL) in chronic bronchitis were studied by using the method in vivo and in vitro. Owing to the importance of (AM) in the processor of chronic bronchitis, effects of TAL on AM functions were investigated. The main contents are divided into some sections as follows:1. Model establishingCombining utilization of BCG (5mg.kg-1, injected through caudal vein) and LPS (200μg, injected through endotracheal intubation one week after BCG injection), the typical morphologic changes of chronic bronchitis were induced after 3 weeks. It is established that the new method by combining utilization of BCG and LPS is convenient and simple for the longitudinal study on the mechanism of initiation and progress of chronic bronchitis.2. Effect of TAL on AM formation and activationTAL significantly inhibited the abnormal increased activation of AM and highly inhibited the change of AM formation.3. Effect of TAL on NF-kB expression and TNF-α IL-1 levels in AM of CB rats. TAL(150、450 mg.kg-1 ig) markedly reduced the increased TNF-a and IL-1 levelsin cultured supernatants of AM in CB rats. TAL(50、150、450 mg.kg-1 ig) obviously decreased the increased expression of NF-kB in AM in a dose dependent manner. The results showed that the anti-inflammatory effect of TAL on CB rats was probably related to its inhibition of cytokines expression in AM.4. Effect of TAL on LTB4 > PGE2 generation in AM of CB rats.TAL(150> 450 mg-kg’1 ig) could not only highly inhibit LTB4 generation but also affect PGE2 production from AM at a dose of 450 mg-kg’1. Results above illustrated that the anti-inflammatory effect of TAL on CB rats was probably correspondent to its reducing of inflammatory mediums expression in AM.5. Effect of TAL on SOD activity and MD A level in AM of CB rats.In order to investigate the relationship between the ROS and chronic bronchitis, SOD and MDA concentrations in AM of CB rats were measured. We found that TAL(150^ 450 mg-kg"1 ig) not only significantly inhibited MDA generation but also increased the SOD production from AM of CB rats.6. Effect of TAL on iNOS expression and NO releasing in AM of CB rats.To supply the anti-inflammatory mechanism study of TAL, we also detected the change of iNOS in AM of CB rats. It is well known that iNOS and NO are important in inflammation and NO could induce lung injury. In this study, it was found that iNOS and NO levels were evidently increased while TAL significantly decreased the increased iNOS and NO levels, which might be another anti-inflammatory mechanism of TAL.7. Effect of TAL on HO-1 activity in lung tissue and expression in AM of CB rats. TAL(150> 450 mg-kg"1 ig) apparently decreased the increased expression of HO-1 inAM and lung tissue of CB rat at mRNA and protein levels in a dose dependent manner. These results showed that the anti-inflammatory effect of TAL on CB rats was probably correspondent to its reducing ROS generation and modulating oxide-antioxide balance.8. Effect of L-Arg and L-NAME on HO-1 mRNA expression in AM of CB ratsL-Arg( 10"5, 10"4 > 10"3 > 10"2 mol/L)could increase HO-1 mRNA expression in AM of CB rats in a dose dependent manner, while L-NAME(250umol/L) reversed the effect of L-Arg on HO-1 expresion. The result suggested that iNOS and its production NO take part in modulation of HO-1 expression. TAL inhibited HO-1 expression in AM by更多还原