Abstract: Objective To investigate the effect of bombesin receptor activated protein(BRAP) on lipopolysaccharide(LPS)-induced mucous hypersecretion in airway and mechamism. Methods After cultivating HBE16 cells in vitro , the constructed p-EGFP-N1-BRAP eukaryotic vector was transfected into the cells,with empty plasmid as a vector control. At the same time in order to LPS as a stimulus to extracellular signal-regulated protein kinase(ERK) specific inhibitor U0126,P38 inhibitor SB203580 and c-jun N-terminal kinase (JNK) inhibitor SP600125 for the intervention factors. The content of ROS, the expression of MUC5AC mRNA and protein, the NF-ΚB activity and cell vitality were detected. Results After transfected pEGFP-N1-BRAP, ROS production was decreased (P < 0.01). The MUC5AC protein production and mRNA level of the group transfected pEGFP-N1-BRAP were significantly decreased as compared with LPS group(P < 0.01), the NF-ΚB activity showed the same trend(P < 0.05). In U0126 group, the expression of MUC5AC was significantly decreased as compared with transfected recombination plasmid group(P < 0.01), the NF-ΚB activity was also significantly decreased(P < 0.05). Conclusions BRAP prevents NF-ΚB activation via ROS/ERK/MAPK signaling pathway,thus reducing LPS-induced mucin5AC production.

Key words: Key words: bombesin receptor activated protein, mucin5AC, extracellular signal-regulated protein kinase, nuclear factor-ΚB