【摘要】 目的观察细胞外信号调节激酶(ERK)、p38分裂原激活的蛋白激酶(p38MAPK)及核因子-κB(NF-κB)在高迁移组蛋白1(HMGB1)诱导大鼠肺泡巨噬细胞表达诱生型一氧化氮合酶(iNOS)中的作用。方法体外培养的大鼠原代肺泡巨噬细胞(PRAMs)分别与ERK抑制剂PD98059、p38MAPK抑制剂SB203580和NF-κB抑制剂PDTC,以及PD98059联合SB203580共孵育2h后,培养基中分别加入重组人HMGB1作用6h。采用逆转录聚合酶链式反应检测培养细胞中iNOSmRNA表达,用Greiss法测定培养上清中NO2-/NO3-的含量。结果PD98059、SB203580和PDTC均可显著下调HMGB1诱导PRAMs表达iNOSmRNA和产生NO(P<0·05)。联合使用PD98059和SB203580可增强抑制iNOSmRNA表达和NO产生(P<0·05)。结论信号分子ERK、p38MAPK和NF-κB均参与了HMGB1诱导大鼠肺泡巨噬细胞表达iNOS和产生NO。更多还原

【Abstract】 Objective To explore roles of extracellular signal-regulated kinase （ERK）1/2,p38 mitogen activated protein kinase（p38 MAPK） and nuclear factor （NF）-κB in expression of inducible nitric oxide synthase （iNOS） in rat alveolar macrophages induced by high mobility group box 1 （HMGB1）. Methods Primary rat alveolar macrophages （PRAMs） cultured in vitro were incubated with PD98059 （inhibitor against ERK）,SB203580 （inhibitor against p38 MAPK）,PDTC （inhibitor against NF-κB）,or PD98059 plus SB203580 for 2 hours,respectively. HMGB1 was added into the cultures and incubated with cells for 6 hours. Total RNA of PRAMs was extracted and iNOS mRNA expression was semi-quantified with reverse transcription-polymerase chain reaction （RT-PCR）. Greiss reaction was applied to determine nitrite/nitrate （NO^-₂/NO^-₃） concentration in PRAMs culture supernatants. Results Expression of iNOS mRNA and NO production in PRAMs culture supernatants were down-regulated by inhibition of ERK or p38 MAPK by PD98059 or SB203580,respectively （P<0.05）. Moreover,inhibition of iNOS expression and NO production was observed after simultaneous pretreatment with PD98059 and SB203580（P<0.05）. Expression of iNOS mRNA in PRAMs and NO production in PRAMs culture supernatants were down-regulated by inhibition ofNF-κB by PDTC（P<0.05）. Conclusion Cellular signal molecules of ERK,p38 MAPK,and NF-κB all participate in the expression of iNOS and NO production in PRAMs induced by HMGB1.更多还原