Abstract: Abstract：Objective To investigate the effects of TRPV4 receptors on the possible signal transduction pathways of rhythmic pressure maintaining airway mucous secretion in airway epithelial cells. Method Using gas/liquid interface vitro culture of human airway epithelial 16HBE cells ,the two devices mimic normal respiratory rhythm generated by the pressure wave and affect the cultured cells.16HBE cells were divide into control group, rhythmic pressure, pressure and Ruthenium red (RR), pressure and Verapamil ,pressure and PKC inhibitors（GF109203x）.The levels of Ca2+concentration was observed by laser confocal, the level of TRPV4 mRNA, pMARCKS and SNAP-23 in culture cells ,and the secretion of MUC (2,5 AC and 5B)in culture medium were detected by RT-PCR ,Western blotting and ELISA respectively. Results Intracellular Ca2+concentration(312.34±17.08) and TRPV4 mRNA(0.63±0.03) level were significantly higher in the rhythmic pressure group than in the control group(196.16±35.06，0.28±0.05) (P all<0.01), which decreased markedly after the intervention of RR (P all<0.01). Due to rhythmic pressure, there were an obvious increase in MUC(2,5AC and 5B) level (0.34±0.08,0.77±0.26,0.49±0.18) pMARCKS and pSNAP-23 protein (0.85±0.42,0.74±0.53). After the preprocessing of verapamil and PKC specific inhibitors, either of MUC level, pMARCKS and SNAP-23 protein were reduced (P all<0.01), which were still higher than the control group (P all<0.01). Conclusion Rhythmic pressure can maintain the secretion of MUC in airway epithelial through activating the TRPV4/Ca2+/PKC/MARCKS signaling pathway.

Key words: Tension-sensitive cation channel 4, Rhythmic pressure wave , Protein kinase C, Mucin