Abstract:

Objective To explore the protective effect of exogenous expansionary pressures generated by continuous positive airway pressure (CPAP) against lung tissues of rats with chronic obstructive pulmonary disease (COPD). Methods Forty Wistar rats were randomly divided into four groups (n=10): control group, sham group, COPD group, and COPD+CPAP group. COPD rat model was developed by inhaling cigarette smoke. The pathological changes of lung tissues of different groups were observed by HE staining. The p-EGFR, p-ERK, and TGF-β1 expressions were detected by immunohistochemistry. The EGFR and TGF-β1 mRNA expressions were measured by RT-PCR. The p-EGFR, ERK, p-ERK, and TGF-β1 protein levels were detected by Western blotting. Results Compared with normal control group, there were significantly bronchopulmonary pathological changes in COPD group, and EGFR, ERK, and TGF-β1 expression levels and the degree of phosphorylation were also significantly enhanced (P<0.01). After CPAP treatment, these indicators were significantly decreased (P<0.01). The differences between the sham group and the normal control group were not statistically significant (P>0.05). Conclusion The improvement of lung inflammation of COPD rats after CPAP treatment may be relevant to the EGFR and TGF-β signaling pathways regulation.

Key words: chronic obstructive pulmonary disease, continuous positive airway pressure, epidermal growth factor receptor, transforming growth factor-β1