矽尘颗粒大小对复制大鼠矽肺模型的影响

Effect of silica dust particle size on duplicate of rat silicosis model

目的比较SiO2粉尘粒径大小对非暴露气管灌注一次性染尘法复制大鼠矽肺模型的影响。方法将购买的SiO2粉尘分为用玛瑙研钵研磨与不做处理两部分,分别将不同粒径的两种粉尘配制成悬液;将大鼠随机分为对照组、研磨实验组和未研磨实验组,实验组均采用非暴露气管灌注SiO2粉尘悬液一次性染尘,对照组以等量灭菌生理盐水代替;三组大鼠分别于1周、2周、3周、4周、6周、8周六个时间点取肺组织,做石蜡切片,行HE、Ⅰ型和Ⅲ型胶原免疫组化染色,镜下观察肺组织形态变化。结果 SiO2粉尘研磨后,粒径小于5μm的达90%以上,未研磨的SiO2粉尘粒径小于5μm的仅占20%;研磨组染尘3周时HE染色可见细胞性结节,8周时纤维组织增生明显,结节增大,肺组织明显破坏,Ⅰ型及Ⅲ型胶原在肺间质广泛阳性表达,大鼠矽肺模型复制成功,未研磨组未能成功复制大鼠矽肺模型。结论研磨可使粒径小于5μm的SiO2粉尘大于90%,采用非暴露气管灌注SiO2粉尘悬液一次性染尘法可以成功复制大鼠矽肺模型,而未研磨粉尘未能引起明显的矽肺形态学变化。

Objective Compare the effect of silica dust particle size on duplicate of rat silicosis model.Methods Purchased SiO2 was divided into two parts,part one was grinded with agate mortar and the other was not,they were prepared to suspension respectively.90 Wistar rats were randomly divided into three groups：control group,the grinded group and without grinding group.The rats of dust exposed groups were given silica suspension by trachea perfusion,and controls were only given physiological saline.1,2,3,4,6 and 8 week later silica exposure,the rats were killed respectively,took the lung tissues for pathological examination（paraffin section,HE and immunohistochemical staining）.Results After grinding,the respriable SiO2 dust（size less than 5 μm）might reach to 90% or more,while the without grinding SiO2 dust the respirable dust was only 20%.The rats of grinded-dust group could successfully silicosis model,the cellular silicotic nodules could be clearly seen 3 weeks later after silicon exposure;8 weeks later,fibrous tissue and silicotic nodules were obviously proliferation,collagen Ⅰ and collagen Ⅲ were widely expressed.But in the rats of dust without grinding group the duplicate of silicosis model was unsuccessful.Conclusion The results suggested that grinding could make more respirable SiO2 dust particle（size less than 5 μm）,which is a important ensurence for successfully silicosis rat model by trachea furfusion method.