吸烟对大鼠肺炎和氧化亚氮合成的影响及相互关系

目的:探讨吸烟对大鼠肺部氧化亚氮(Nitricoxide,NO)合成的影响机制与炎症关系。方法:54只Wistar大鼠随机分为对照组(9只)、吸烟组(45只),平均分配在1、2d、1、2周及2月共5个时间点吸烟观察。吸烟组的大鼠置入吸烟箱内每天吸烟2次,每次45min,对照组放入无烟箱内。两组大鼠检测有关肺部的炎症指标和NO合成的变化。结果:(1)吸烟组支气管肺泡灌洗液(BALF)中细胞总数,中性粒细胞数显著高于对照组;BALF中白细胞介素(IL)8含量(pg/mL),吸烟组在1、2周及2月有显著性增高(P<0.05),对照组变化不大。(2)吸烟组大鼠呼出气中NO的含量显著低于对照组(P<0.05)。(3)相关分析显示:吸烟1周后NO的浓度与IL8的含量成负相关(r=-0.671,P<0.05),IL8的含量与中性粒细胞数成正相关(r=0.752,P<0.05)。结论:吸烟导致的大鼠肺炎反应与肺组织NO的合成减少有关。

Effect of Smoking on Nitric Oxide Synthesis and Its Relationship with Pulmonary Inflammation in Rats

Objective:To study the effect of smoking on the synthesis of nitric oxide (NO) and its relationship with pulmonary inflammation in rats. Methods: 54 Wistar rats were randomly divided into one control group (9 rats) and 5 smoking groups based on course of smoking (1 day, 2 days, 1 week, 2 weeks and 2 months), with 9 rats in each, receiving cigarette smokes for 45 minutes twice daily. Measures of pulmonary inflammation and NO synthesis were assessed in rats. Results: 1) The total cell counts and neutrophil counts in BALF of smoking groups were markedly higher than that of control group; IL-8 levels (pg/mL) in BALF of smoking groups (1 week, 2 weeks and 2 months) were significantly increased (P<0.05); 2) Smoking rats exhaled less NO as compared with controls (P<0.05); 3) In smoking groups from 1 week to 2 months, the level of IL-8 was positively correlated with neutrophil count in BALF (r=-0.671, P<0.05) and negatively correlated with exhaled NO (r=0.752, P<0.05). Conclusion: The inflammation of lung tissue in smoking rats may be closely related to the inhibition of NO.