Relationship between connective tissue growth factor expression in pulmonary arteries and pulmonary artery remodeling induced by smoke

AIM:To study the relation between smoke-induced pulmonary artery remodeling and connective tissue growth factor(CTGF)expression in pulmonary arteries.METHODS:Twenty-four male Wistar rats were randomly assigned into control group and smoke exposure group,and the latter was further divided into three time points of 1,2,3 months.Pulmonary artery remodeling was observed by Hematoxylin-Eosin staining,and collagen contents were investigated by sirius red staining.Immunohistochemistry methods were performed to determine CTGF protein expression in pulmonary artery smooth muscle.The expressions of CTGF mRNA in pulmonary arteries were evaluated by RT-PCR.RESULTS:(1)The pulmonary artery WA% in four groups were(30.5±1.6)%,(43.3±2.0)%,(49.3±1.2)%,(60.3±2.9)%.Compared to control group,significant increases in smoke exposure groups were observed.(2)Collagen was abnormally deposited in pulmonary artery walls of smoke exposure groups.(3)CTGF mRNA expressions in pulmonary artery walls were(0.032±0.012),(0.644±0.351),(2.749±0.458),(2.337±0.149).There were markedly differences among four groups.(4)CTGF protein expressions in pulmonary artery walls were(0.081±0.013),(0.139±0.016),(0.307±0.016),(0.319±0.017).There were markedly differences among four groups.(5)Both CTGF mRNA and protein were positively correlated with WA%(r=0.841,P0.01;r=0.902,P0.01).CONCLUSION:Pulmonary artery remodeling happens in early period after smoke exposure,and becomes worse.CTGF expressions in pulmonary arteries in smoke exposure groups obviously increase,and may play an important role in pulmonary arteries remodeling.