[The expression variations of connective tissue growth factor and cyclinD1 in pulmonary vascular remodeling induced by cigarette smoke in rats].

OBJECTIVE: To investigate the expression variations of connective tissue growth factor (CTGF) and cyclin D1 in pulmonary vasculature in rats exposed to cigarette smoke and their roles in pulmonary vascular remodeling. METHODS: Twenty-four male Wistar rats were randomly divided into 4 groups: 1 control group (C group) and 3 smoke exposure groups (S2w, S4w, S8w group). Arterial partial pressure of oxygen was measured. Pulmonary artery remodeling was observed by Hematoxylin-Eosin staining and the percentage of muscularised small pulmonary arteries. Immunohistochemistry methods were performed to observe CTGF and cyclin D1 expressions in pulmonary artery smooth muscle. Real time quantitative RT-PCR and Western blot analysis were used for detection of mRNA and protein expressions in pulmonary artery smooth muscle. RESULTS: There was no significant difference in arterial partial pressure of oxygen among all groups. The percentage of muscularised small vessels and W/T were significantly increased in S2w, S4w and S8w group compared to control group (P < 0.05). Compared to control group, significant increases of CTGF and cyclinD1 expressions in smoke exposure groups were observed (P < 0.05). The expressions of CTGF and cyclinD1 were significantly positively correlated with the severity of pulmonary vascular muscularization, and there was statistically positive correlation between the expression of CTGF and cyclinD1. CONCLUSION: CTGF and cyclinD1 expressions significantly were upregulated in pulmonary arteries from rats exposed to cigarette smoke (2-8w) and there was a significant positive correlation between their expressions. Their expression variations may be associated with abnormal proliferation of pulmonary artery smooth muscle cells induced by cigarette smoke.