【摘要】 探讨肿瘤坏死因子α (TNFα)和γ干扰素(INFγ)对大鼠膀胱平滑肌细胞诱导性一氧化氮合酶(iNOS )的影响 .将TNFα (1nmol·L- 1)或INFγ(5 0kU·L- 1)分别或同时加入膀胱平滑肌细胞培养液 ,2 4h后测定细胞培养液中一氧化氮 (NO)水平 ,并用Western印迹方法检测iNOS的表达 .结果显示 ,TNFα或INFγ单独不能诱导iNOS表达 ,也不能引起NO水平显著提高 .但当TNFα和INFγ联合诱导细胞 2 4h ,则细胞培养液中NO水平明显升高 ,用Western印迹分析可见iNOS表达 ,说明TNFα和INFγ具有协同诱导作用 .在TNFα和INFγ加入膀胱平滑肌细胞前 30min ,加入NOS抑制剂L 氮 精氨酸甲酯 (L NAME) ,可显著抑制TNFα和INFγ对NO的生成诱导 .结果提示 ,TNFα和INFγ联合应用可激活膀胱平滑肌细胞iNOS .更多还原

【Abstract】 The effects of tumor necrosis factor alpha (TNFα) and interferon gamma (IFNγ) on inducible nitric oxide synthase (iNOS) in rat bladder smooth muscle cells (SMC) were investigated. When bladder SMC were induced with TNFα(1 nmol·L -1 ) or IFNγ(50 kU·L -1 ) alone or their combination for 24 h, nitric oxide (NO) levels were determined, and iNOS was detected by Western blot. The results indicated that TNFα, or IFNγ alone did not induce iNOS expression and NO production. However, NO levels significantly increased when the cells were exposed to the combined TNFα and IFNγ for 24 h, and the iNOS protein with around 125 kU of molecular weight was also detected by Western blot analysis, suggesting that TNFα and IFNγ synergistically induce iNOS expression and NO production in bladder SMC. When NOS inhibitor N G nitro L arginine methyl ester (L NAME, 0.1 mmol·L -1 ) was added into bladder SMC 30 min prior to addition of the combined TNFα and IFNγ, it was found that NOS inhibitor significantly decreased cytokines induced NO production. The findings suggest that iNOS in bladder SMC be activated by combined TNFα and IFNγ.更多还原