泼尼松对MCP-1及IL-8在COPD大鼠气道表达的影响

目的研究单核细胞趋化蛋白-1（MCP—1）及白细胞介素8（IL-8）在慢性阻塞性肺疾病（COPD）大鼠气道的表达及泼尼松对其的影响。方法Wistar大鼠随机分为3组：正常对照组（A组）、COPD模型组（B组）和泼尼松干预组（C组）。采用单纯熏香烟法建立COPD模型，泼尼松隔日灌胃，计数支气管肺泡灌洗液（BALF）中细胞数，以酶联免疫吸附法（ELISA）测定BALF和血清中的MCP-1及IL_8浓度。肺组织切片观察形态学改变，采用图像分析系统分析肺气肿程度。结果B组气管及支气管的慢性炎症改变及肺气肿改变较C组明显。B组BALF中MCP-1、IL-8浓度、细胞计数及血清中IL-8浓度均高于A组，但血清MCP-1的升高无统计学差异。与B组相比，C组BALF中MCP—1、IL-8浓度及细胞计数均下降，但血清中MCP-1及IL_8的浓度下降无统计学意义。B组BALF中MCP-1浓度与肺泡巨噬细胞（AM）数日及BALF中IL_8与中性粒细胞数目呈正相关（r=0．861，P〈O．01；r=0.735，P〈O．05），但血清中MCP-1、IL-8浓度与BALF中的细胞数目均无相关性。结论MCP-1和IL-8与COPD的气道炎症密切相关。泼尼松早期干预可通过对MCP-1、IL-8及AM、中性粒细胞的抑制而减轻COPD气道炎症。

The Effect of Prednisone on Expression of MCP-1 and IL-8 in airway of rats with COPD

Objective To explore the role of MCP-1 and IL-8 in the pathogenesis of COPD and the effects of pred- nisone on COPD. Methods Wistar rats were randomly divided into three groups （Group A.. normal control rat, Group B： COPID model, Group C.. preventive group with prednisone）. Rat COPD model was established by exposing the rates to cigarette smoke daily. Prednisone was given to the rats of Group C through stomachal injection on alternate days. Af- ter four months cell counts in bronchoalveolar lavage fluid（BALF） were examined and the levels of MCP-1 and IL-8 in BALF and serum were measured by ELISA. Lung tissue sections stained by HE were observed to study the alternation of morphology. Results The changes of chronic inflammation of the trachea and bronchi and pulmonary emphysema were more serious in group B, compared with those in group C. The level of MCP-1 and IL-8, total cell counts, AM counts and neutrophil counts in BALF of group B were significantly higher than those of group A（P〈0.01）. The levels of IL-8 in serum o group B were also significantly higher than those of group A. After the treatment with prednisone, significant decrease in the level of MCP-1 and IL-8 in BALF was found in group C as compared to those of group B. Positive correla- tions were demonstrated between the level of MCP-land AM counts （r=0. 861 ,P＇（O. 01）, the level of IL-8 and neutro- phil counts （r=0. 735, P（0.01）. Conclusion There is a close correlations between MCP-1, IL-8 and airway inflamma- tion in COPD. Prednisone may relieve airway inflammation in COPD by inhibiting the action of MCP-1, IL-8, AM and neutrophil.