Establishment Of A Model Of Acute Lung Injury Induced By Pm2.5 In Rats By Nasal Instillation

72 SD rats were randomly divided into 4 groups (18 in each group), namely, control group, PM2.5 low dose group (PML, 0.25 mg/mL), PM2.5 medium dose group (PMM, 0.5 mg/mL), PM2.5 high dose group (PMH, 1 mg/mL). The animal model was established by nasal drip method, and the drop was given on the day 1, 7, 14, 21 and 28. Six rats were sacrificed in each group at 24 hours after the third, fourth and fifth nasal instillation. The lung pathology, lung wet to dry weight (W/D) ratio, lung permeability index and oxygenation index were observed before and after modeling, which were used to evaluate whether the model is built successfully. Compared with the control group after the fifth nasal instillation, the PMM group showed severe lung injury, significant inflammatory response, the lung wet to dry weight (W/D) ratio and lung permeability index were significantly decreased (P < 0.05), the oxygenation index increased significantly (P < 0.05). The ALI model of rats prepared by nasal instillation with PM2.5 suspension at a concentration of 0.5 mg/mL is consistent with the main features of ALI animal model, the optimized rat model was successfully established.