Expressions of and the effect of smoking on vascular endothelial growth factor and induced nitric oxide synthase in lung tissues of chronic obstructive pulmonary disease patients

Objective To investigate the expressions of and the effect of smoking on vascular endothelial growth factor(VEGF)and induced nitric oxide synthase(iNOS)in lung tissues of chronic obstructive pulmonary disease(COPD)patients.Methods The peripheral lung tissues were obtained from 46 patients with lung carcinoma.They were divided into three groups according to their habit of smoking and lung function,19 smokers with moderate COPD,12 smokers and 15 nonsmokers with normal lung function. The expression of VEGF and iNOS was detected by immunohistochemistry.Results Expressions of VEGF and iNOS were increased in lung tissues of smokers without COPD(1.50±0.39,1.45±0.41)compared with nonsmokers without COPD(1.18±0.33,1.09± 0.41)(each P0.05),and were significantly increased in lung tissues of smokers with moderate COPD(2.19±0.51,2.39±0.45)compared with nonsmokers without COPD(each P0.01).The expression of VEGF in lung tissues was significantly correlated with the expression of iNOS(r = 0.78,P0.01),but was inversely correlated with FEV_1(r= -0.67 ,P0.01).Conclusions Expressions of VEGF and iNOS were upregulated in lung tissues of smokers and patients with moderate COPD.Overexpression of iNOS and VEGF may participate in the mechanism of airway and vascular remodeling,and airflow limitation in COPD.