肺染木尘对大鼠肺脏器系数及支气管肺泡灌洗液影响的实验研究

Experimental study of the effect of wood dust on rats' pulmonary organ coefficient

目的探索木尘对肺组织的损伤。方法以0、100、400、800mg/kg剂量木尘和博来霉素阳性对照通过气管内注入的方式对大鼠进行染尘,于第7、15、30、60天对肺泡灌洗液进行分析,对肺脏器系数进行测定。结果各木尘染尘组不同时间大鼠体重、肺脏器系数、灌洗液中的蛋白质与阴性对照组比较差异均无显著性(P>0.05),但第7天各染尘组支气管肺泡灌洗回收液量(BALF)中白细胞总数及中性粒细胞均较阴性对照组显著增高,淋巴细胞较阴性对照组显著降低,第15天后基本恢复正常;第7、15天木尘各剂量组BALF中TNF-α值均显著高于阴性对照组,第30天基本恢复正常。结论木尘能引起早期大鼠急性肺泡内炎症,炎症细胞释放的肿瘤坏死因子TNF-α水平增加。

Objective To investigate the effect of wood dust on rats＇ pulmonary tissue. Methods The Wistar rats in five groups were contaminated by wood dust via trachea infusion at the dose of 0,100, 400 , 800 mg/kg, and bleomycine was used as positive control group. The bronchoalveolar lavage fluid （BALF） was analyzed at the 7th, 15th, 30th and 60th day, and pulmonary organ coefficients were detected. Results There was no obvious difference in rats＇ body weight, pulmonary organ coefficient, and protein of BALF between wood dust groups and negative control group（ P 〉 0.05）, but the counts of white cells and neutrophilic granulocytes were obviously higher than those of negative control group on the 7th day, however, the counts of lymphocytes were obviously lower than those of negative control group on the 7th day, and which returned to normal levels on the 15th day ; the levels of TNF-a in BALF of experimental groups and positive control group were obviously higher than those of negative control group on the 7th and 15th day, but there was no significant difference on the 30th day. Conclusion The wood dust could cause acute bronchoalveolar inflammation, and the levels of TNF-α released by inflammation cells will increase.