钙激活性CI^-通道阻断剂对气道平滑肌细胞增殖的抑制作用

Inhibitory effect of niflumic acid on the proliferation of airway smooth muscle cells

【目的】探讨钙激活性CI-通道阻断剂尼氟灭酸(NFA)对平滑肌细胞(ASMCs)增殖的影响及机制。【方法】采用[3H]-TdR掺入法检测不同剂量NFA对ASMCs增殖活性的影响。观察NFA及硝苯地平对组胺致ASMCs中[Ca2+]i变化的影响。间接免疫荧光法观察NFA对ASMCs表达MAPK蛋白的影响。【结果】10μmol/L和50μmol/L NFA组细胞的活性明显低于对照组,并且高浓度50μmol/L NFA组比低浓度10μmol/LNFA组更显著,表现出剂量依赖性。对照组ASMCs胞浆和胞核呈现亮绿色荧光,胞膜周围较淡,加入激动剂组胺后,荧光亮度逐渐增强。相反,当同时存在NFA或硝苯地平干预时,镜下观察荧光强度变化不够明显。间接免疫荧光染色结果表明,培养24 h后,对照组中ASMCs细胞沿梭形胞浆出现大斑片状亮绿色荧光,而NFA干预组细胞表现为弱绿色荧光,胞浆内分布区域局限。【结论】NFA能有效抑制培养ASMCs的增殖活性,可能是通过阻断钙激活性CI-通道对[Ca2+]i的正反馈效应,以及降低MAPK的表达来实现的。

[Objective] The inhibition and mechanism of NFA on the proliferation of airway smooth muscle cells （ASM- Cs） were investigated. [Methods] The effect of NFA on the proliferation of primary ASMCs by [^3H] -TdR incorporation method were examined. The [Ca^2＋] i in ASMCs exposed to histamine was observed with confocal laser scanning microscope, and the opposed effects of NFA and nifene 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 cell 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. [Concision] NFA could inhibit the proliferation of ASMCs probably by reducing [Ca^2＋ ] i and the expression of MAPK.