| Objective①To detect the progress of airway remodeling and pulmonary vascular reconstruction in lung tissue at various stages of chronic obstructive pulmonary disease (COPD) dynamically.②To understand the nuclear factor-κB( NF-κB) dynamic changes in various stages of COPD, as well as the relation among NF-κB, airway reconstruction and pulmonary vascular remodeling.③To observe the effect of NF-κB inhibitor pyrrolidine dithiocarbamate (PDTC) in airway reconstruction and pulmonary vascular remodeling at various stages of COPD, analysis the effect of the drug.Methods 48 SD rats were divided into 8 groups randomly, integrating the experimental group and the medicine intervention group separately, each group of 6. The experimental group: A, B, C, D. Healthy control group(Group A):rats were bred for 4 weeks in normal circumstance. Having a test 4 weeks later.Chronic bronchitis group (Group B): 200μg LPS was instilled intratracheally once at first and forteenth day for all rats, a total of 4 weeks. COPD group(Group C): 200μg LPS was instilled intratracheally once at first and forteenth day for all rats. Then these rats were exposed to cigarette smoke 1h/d for 4 weeks. Pulmonary hypertension from COPD group(Group D): 200μg LPS was instilled intratracheally once at first and forteenth day and the rats were exposed to cigarette smoke 1h/d for 4 weeks. In last 2 weeks chronic hypoxia(FiO2=0.18)8h/d were performed simultaneously. The PDTC medicine intervention group: A1(Blank control group), B1(Chronic bronchitis intervention group), C1(COPD intervention group), D1(Pulmonary hypertension from COPD intervention group). The animal model manufacture following each correspond -ing group, Each group had the intraperitoneal injection of PDTC from fifteen day, doses of 100mg ? kg-1 ? d-1. A1 group was used the same dose of normal saline replace PDTC. We studied airway resistance, pulmonary hemodynamic changes,and the structure of right ventricular wall. HE strains and triple strains were done, observing the airway wall remodeling and the changes of small pulmonary arterial morphologic. The positive expression of NF-κB in lung tissue were detected by immunohistochemistry(IHC), RT-PCR, Western blot.Result①Compared to the group A, the airway resistance in group C and D were significantly increased(P <0.05).②The right ventricular systolic pressure(RVSP), mean pulmonary arterial pressure(mPAP)and the ratio of the weight of right ventricle/left ventricle and septum(RV/LV+S) were higher in group C, D than group A(P <0.05). Compared to the group C, the RVSP in group D were increased(P <0. 05), there was no difference of RV / LV + S between group C and group D (P >0.05). Compared to the group C, D, the RVSP, mPAP in group C1, D1were significantly decreased (P <0. 05). RV / LV + S in group D is higher than in group D1(P <0. 05).③with the group A, the ratio of bronchial wall over external diameter(MT%) and the ratio of bronchial wall area over total area (MA%) were significantly higher in group C, D (P <0.05), there was no difference between C and D(P > 0.05). Compared to the group C, D, the MT%, MA% in group C1, D1were significantly decreased (P <0.05).④The muscularization of intra-alceolar arteries in group C, D were significantly apparent compared with group A(P <0.05). The cross-sectional medial vascular wall area of pulmonary arteries were increased significantly in group D(P <0.05). Compared to the group C, D, the percentage of muscular arteries in C1, D1were lower(P <0.05). The ratio of vascular wall over external diameter (WT%). The ratio of vascular wall area over total area (WA%) in D1 group was decreased than the experimental group(P <0.05).⑤Immunohistochemistry showed that, the expression of NF-κB protein in groupC, D were stronger than group A, B (P <0. 05). Compared to the experimental group, the expression of NF-κB in groupC1, D1 were decreased (P <0. 05).⑥RT-PCR displayed that, compared with the group A, the expression of NF-κB mRNA were increased in group C, D (P <0.05). There were also differences between group C and group D (P <0.05). The expression of NF-κB mRNA in C1, D1were lower than in group C, D (P <0.05).⑦Western Blot showed that compared with the group A, the expression of NF-κB protein in group C, D were significantly increased(P <0.05). The expression of NF-κB protein in group D is higher than group C(P <0.05). Compared to the group C, D, the expression of NF-κB protein in C1, D1were decreased (P <0.05).⑧The expression of NF-κB were correlated positively with the index MT%, MA% of airway remodeling(P <0.01), and the index WT%, WA% of pulmonary vascular remodeling(P <0.01).Conclusions①With the progression of the disease, the airway remodeling and pulmonary vascular reconstruction had appeared progressive aggravation. They showed that, the percentage about muscularization of intra-alceolar arteries and the cross-sectional medial vascular wall area of pulmonary arteries were increased significantly, the airway resistance and the thickness of the smooth muscles in the bronchial wall were higher.②With the progression of COPD, the expression of NF-κB was increased in lung tissue, there may have some relevance among the expression level of NF-κB, airway remodeling, and pulmonary vascular reconstruction.③Compared with the experimental group, PDTC may be inhibit the expression of NF-κB, improve the airway remodeling and pulmonary vascular reconstruction effectively, prevent the formation of pulmonary hypertension partly. |
