Synthesis of nitric oxide and nitrosamine by immortalized woodchuck hepatocytes.
Synthesis of nitric oxide and nitrosamine by immortalized woodchuck hepatocytes.
复制标题
永生土拨鼠肝细胞合成一氧化氮和亚硝胺。
DOI：
10.1093/carcin/14.8.1609
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发表时间：
1993
期刊：
影响因子：
4.7
通讯作者：
Tennant,BC
中科院分区：
文献类型：
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作者：
Liu,RH;Jacob,JR;Hotchkiss,JH;Tennant,BC
土拨鼠（旱獭monax）肝细胞，这是永生化的猿猴病毒40大T抗原（SV 40标签）产生一氧化氮（NO;测量为亚硝酸盐）在体外从L-精氨酸（L-Arg）脂多糖（LPS）处理后。NO合成与L-Arg和LPS浓度相关，并在1.0 mM L-Arg和1.0 μg/ml LPS下达到平台。LPS刺激的细胞亚硝化吗啉形成N-亚硝基吗啉（NMOR）在L-Arg的存在下，在pH 7.4。LPS刺激肝细胞后，NMOR的产生增加了7倍，在有LPS和L-Arg存在的细胞培养液中检测到N-亚硝基二甲胺（NDMA），NO合成酶抑制剂NG-单甲基-L-arginine可抑制NO和NMOR的产生，表明NO和亚硝化剂是通过L-Arg-nitric oxide途径产生的。这些数据是第一次报道NO和N-亚硝胺生产的永生化肝细胞和确认早期的工作表明，原代肝细胞形成NO的文化。提示肝内N-亚硝基化合物和/或NO的形成可能是肝细胞癌的一个致病因素。永生化土拨鼠肝细胞可作为研究L-Arg-NO通路及其在肝癌发生中作用的体外模型。
Woodchuck (Marmota monax) hepatic cells, which were immortalized by the simian virus 40 large T antigen (SV40 Tag) produced nitric oxide (NO; measured as nitrite)in vitrofrom L-arginine (L-Arg) after lipopolysaccharide (LPS) treatment. NO synthesis was related to L-Arg and LPS concentration and plateaued at 1.0 mM L-Arg and 1.0 μg/ml LPS. LPS-stimulated cells nitrosated morpholine to formN-nitrosomorpholine (NMOR) in the presence of L-Arg at pH 7.4. NMOR production increased 7-fold in LPS stimulated cells compared to unstimulated hepatocytes.N-nitroso-dimethylamine (NDMA) was detected in the cell culture medium in the presence of LPS and L-Arg but without added dimethylamine.NG-monomethyl-L-arginine, a selective inhibitor of nitric oxide synthase, inhibited formation of NO and NMOR, indicating that NO and nitrosating agents were formed via the L-Arg-nitric oxide pathway. These data are the first to report NO andN-nitrosamine production by immortalized hepatocytes and confirm earlier work showing that primary hepatocytes form NO in culture. This suggests that hepatic formation ofN-nitroso compounds and/or NO could be an etiologic factor in hepatocellular carcinoma. Immortalized woodchuck hepatic cells may be useful asin vitromodels to study the L-Arg-nitric oxide pathway and its possible role in liver carcinogenesis.