Objective: To detect the effect of p38 mitogen activated protein kinase (p38MAPK) and cyclooxygenase-2 (COX-2) on the expression of mucin5AC (MUC5AC) in human nasal mucosa induced by histamine in vitro, and to investigate the pathogenesis of mucus hypersecretion in allergic rhinitis (AR).
Method: Western blot was performed to detect the protein expressions of p38MAPK, COX-2 and MUC5AC in nasal mucosa induced by histamine or blocked by selective inhibitors of p38MAPK and COX-2 of different concentration gradient.
Result: Weak expressions of p38MAPK. COX-2 and MUC5AC were detected in normal nasal mucosa in vitro. The protein expressions of p38MAPK. COX-2 and MUC5AC increased in nasal mucosa induced by histamine in a dose-dependent manner. The histamine induced protein expressions of COX-2 and MUC5AC were dose-dependently attenuated by selective inhibitor of COX-2, namely NS-398. No apparent influence of NS-398 on the expression of p38MAPK was observed. The histamine induced protein expressions of p38MAPK, C()X-2 and MUCbAC dose-dependently decreased after nasal mucosa was treated by selective inhibitor of p38MAPK, namely SB203580. And no significant change of MUC5AC protein expression induced by NS-398 or SB203580 was observed.
Conclusion: Our findings indicated that the histamine-induced increased expression of MUC5AC by activated p38MAPK/COX-2 may be a possible pathogenesis of mucus hypersecretion in AR.