染矽尘大鼠BALF中炎性细胞改变研究

目的]探讨不同染尘剂量大鼠矽肺模型支气管肺泡灌洗液(BALF)中炎性细胞的变化规律,为矽肺的发病机制提供可靠依据。方法]2009年5～8月采用一次性气管内灌注二氧化硅(SiO2)粉尘的方法制作大鼠矽肺模型。大鼠随机分为对照组和模型组(15、30、60mg/ml),分别在1、3、7、14、21、28d将大鼠处死,采用在体全肺灌洗法收集BALF,光学显微镜下计数白细胞总数,瑞士吉姆萨染色法进行白细胞分类计数。结果]模型组大鼠BALF中白细胞总数在大鼠染尘1、3、21、28d较对照组均增高,其中高剂量组和中剂量组较对照组差异有统计学意义(P<0.05);在7、14d仅高剂量组较对照组差异有统计学意义(P<0.05)。各剂量组在大鼠染尘1、3、7、14、21、28d,巨噬细胞、中性粒细胞和淋巴细胞均较对照组增高,巨噬细胞在染尘1、3、7、21、28d均增高;中性粒细胞在1～14d显著增高(P<0.05),淋巴细胞在7～28d明显增高(P<0.05);各剂量组在染尘1、3、7、14、21、28d尘细胞数均增高。结论]染尘大鼠早期主要表现为炎症反应,炎症细胞(巨噬细胞、中性粒细胞、淋巴细胞和尘细胞)呈规律变化,且尘细胞具有较好的剂量-反应关系,对矽肺的预防和早期诊断具有很大的意义。

Study on Changes of Inflammatory Cells in BALF of Rats Exposed to Silica Dust

Objective]To explore the change of inflammatory cells levels in BALF of rats with different exposure doses,so as to provide reliable basis for the pathogenesis of silicosis.Methods]Rats were one-time instilled with silica as silicotic models.They were divided into control group and model group(15 mg/ml、30 mg/ml、60 mg/ml)randomly.On 1,3,7,14,21 and 28 d after establishment of the animal model,rats were sacrificed,By douching whole-lung in vivi,the BALF.Centrifugal were collected,and than the total leukocytes In the optical microscope.and the classification with Wright,s Giemsa staining method were recorded.Results]In BALF,compared with the control group,leukocytes were significantly higher on 1,3,21,28 d,the diffenrences in high-dose group and medium-dose group were significant(P<0.05);and on 7d and 14d,this phenomenon was not obvious,only the high-dose group was statistically significant(P<0.05).Classification result of BALF represented that compared with the control group,the number of macrophages、neutrophils and lymphocytes all increased on 1,3,7,14,21,28 d.The number of macrophages significantly increased on 1,3,7,21,28 d;The number of neutrophils was significantly higher in 1-14 d(P<0.05);the number of lymphocytes was significantly higher on 7-28 d(P<0.05);In model group at each time point the number of dust cells was significantly higher(P<0.05).Conclusion]Inflammatory reaction is maily performanced for the rats exposed to silica dust,inflammatory cells(macrophages,neutrophils,lymphocytes and dust cell) changed regularly,and the dust cells tend to increase with the increase of dose dust,and it has a good dose-response relationship.The variation of the inflammatory cells is significant for the prevention and early diagnosis of silicosis.