高浓度大气PM_(2.5)混悬液对大鼠鼻黏膜及上颌窦黏膜影响研究

Effects of high-concentration PM_(2.5) suspension on the nasal and maxillary sinus mucosa of rats

目的:研究大气中PM_(2.5)对大鼠鼻黏膜及上颌窦黏膜的影响,并探究其中两种主要黏蛋白muc5ac和muc5b的基因表达情况。方法:使用四通道PM_(2.5)采样器,采集大气中的PM_(2.5),用0.9%氯化钠注射液配制成混悬液,实验组大鼠每天鼻腔滴注500μl浓度为0.004μg/μl的PM_(2.5)混悬液,对照组滴注等剂量0.9%氯化钠注射液,分别在7、14、30d取鼻黏膜及上颌窦黏膜。通过HE染色,光学显微镜下观察鼻黏膜及上颌窦黏膜的组织形态学,并通过荧光定量PCR检测muc5ac和muc5b的基因表达情况。结果:PM_(2.5)混悬液滴注30d后,鼻黏膜上皮完整性被破坏,纤毛消失,黏膜下腺体增生,炎性细胞浸润,上皮层出现鳞状化生现象,同时其中两种主要的粘蛋白基因muc5ac和muc5b表达升高;滴注7、14d的鼻黏膜均未出现明显病变。而对于上颌窦黏膜,滴注30d后仅表现出轻微的炎症反应,上皮完整性受损,黏膜下少量炎细胞浸润,其中muc5ac表达降低,muc5b的表达未受影响;滴注7、14d同样未导致明显病变。结论:大气PM_(2.5)混悬液达到一定浓度时,接触大鼠鼻黏膜及上颌窦黏膜会导致其受损,其中鼻黏膜损伤更加严重。

Objective： To investigate the effects of PM2.5 on the nasal and maxillary sinus mucosa of rats, and explore the gene expression level of muc5ac and mucSb. Methods： airborne PME.s with a four-inlets PMzs sampler were collected and made up the PM2.5 suspension with sterile saline were made. In experimental group, rats were dripped with the PM2.5 suspension through nasal passage, and in control group, they were dripped with equal dose of sterile saline. After dripping PM2.5 suspension for 7, 14 and 30 days, the nasal and maxillary sinus mucosa were collected for morphology analysis and the gene expression of muc5ac and muc5b were evaluated. Results： After dripping the PM2.5 suspension by nasal passage for 30 days, significant morphologic alterations of the nasal mucosa were observed, including epithelial integrity destroyed, cilia disappeared, gland hyperplasia, inflammatory cell infiltration, and squamous metaplasia. The expression of muc5ac and muc5b in nasal mucosa was up-regulated significantly. There were no obvious changes of nasal mucosa neither at 7th day nor at 14th day. Nevertheless, there was only slight inflammation occurred in the maxillary sinus after PM2.5 instilled for 30 days, including epithelial integrity destroyed and inflammatory cell infiltration. The muc5ac expression was decreased, and there was no difference of muc5b expression between the two groups. Conclusions： PM2.5 suspension could induce patho-logical injury in nasal and maxillary sinus mucosa of rats, and the injury of nasal mucosa was more severe.