The expression of connective tissue growth factor (CTGF) in the lung tissue of COPD rat models

Objective To study the expression of connective tissue growth factor(CTGF)in rat model with chronic obstructive pulmonary disease(COPD). Methods The rat models(model groups) of COPD were established by passive smoking and intratracheal instillation of lipopolysaccharide (LPS). CTGF mRNA and protein level were detected in lung tissue in each group by RT-PCR and im-munohistochemistry methods. The distribution and the ratio of type I to type Ⅲ collagen in the lung tissue were determined by using a Sirius red-polarizing microscopy morphometry method. With semi-quantitative analysis, pathomorphology of COPD rat lung tissue was evaluated. Results CTGF mRNA level was not detected in control group. But it manifested at 7 d,with the peak expression at 14 d,descended then at 21 d, keeping at a high level at 28 d. CTGF protein expression increased gradually with smoking exposure elapsing,as compared with control and 7 d group. Conclusion CTGF may play an important role in the formation and development of COPD.