RESUMO
AIM: Niflumic acid (NFA) is known as a kind of inhibitor of calcium-activated chloride channel. The inhibition and mechanism of NFA on the proliferation of airway smooth muscle cells (ASMCs) were investigated. METHODS: Using [ 3H]-TdR incorporation method, we examined the effect of NFA (at concentration of 10 and 50 ?mol/L) on the proliferation of primarily ASMCs from BALB/c mouse. With confocal laser scanning microscope the [Ca 2+ ]i in ASMCs exposed to histamine was observed, and the opposed effects of NFA and nifedipine on histamine were also checked. Finally the effect of NFA on expression of MAPK in ASMCs was examined by indirect immunofluorescent assay. RESULTS: Compared with control group, the proliferation of NFA group was reduced markedly with dependent concentration. Histamine significantly improved the [Ca 2+ ]i in ASMCs, but NFA and nifedipine showed the inhibition on the effect of histamine. NFA reduced the level of MAPK expression in ASMCs. CONCLUSION: It is demonstrated that NFA inhibits the proliferation of ASMCs by reducing [Ca 2+ ]i and the expression level of MAPK. [