Objective To establish a rat model of chronic obstructive pulmonary disease (COPD) by smoking, protease infusion and a combination of the two methods, and evaluate the effect of the model from the level of inflammation, imaging and pathology, and compare the three modeling methods.
Methods The COPD rat models were established by smoking, protease infusion and the combination of the two methods. There were 60, 30 and 30 rats in each group, and 20 rats in the control group. The weight of rats was measured every week. The rats in the smoking group and the control group received cytokine detection, micro CT examination and pathological examination at 24h, 1,2,4,8,12,16,20,24 weeks after modeling, and the rats in the protease group and protease+smoking group received cytokine detection, micro CT examination and pathological examination at 24h, 1,2,4,8,12 weeks after modeling. Analysis of variance or Kruskal Wallis H test were used for statistical analysis.
Results From the 7th week, the weight growth of rats in the smoking group and protease+smoking group was significantly slower than that of the control group (P<0.05). The level of interleukin-10 in protease group and protease+smoke group was significantly lower than that in control group at 24h, 1,2,4 weeks (P<0.05). The concentration of matrix metalloproteinase-9 in protease group and protease+smoke group at 24h was significantly higher than that in control group (P<0.05). Emphysema changes were observed in Micro CT images and pathological images of rats in protease group, protease+smoking group at week 4 and smoking group at week 8.
Conclusion The rat COPD model can be successfully established by smoking, protease and protease+smoking. Micro CT can reflect the pathological changes of lung sensitively and truly.