<i>N</i>-Methylcarbamoylated Valine of Hemoglobin in Humans after Exposure to <i>N,N</i>-Dimethylformamide: Evidence for the Formation of Methyl Isocyanate?
作者:Heiko Udo Käfferlein、Jürgen Angerer
DOI:10.1021/tx000230r
日期:2001.7.1
N,N-Dimethylformamide (DMF) is reported to cause testicular germ-cell tumors in exposed workers. The reports, however, are not in line with results obtained in animal and in vitro experiments, where DMF was shown not to be mutagenic and also not to be carcinogenic. Considerable interest raised on the formation of a reactive intermediate, presumably methyl isocyanate (MIC), during metabolism of DMF
据报道,N,N-二甲基甲酰胺(DMF)会引起裸露工人的睾丸生殖细胞肿瘤。但是,这些报道与在动物和体外实验中获得的结果不符,在动物和体外实验中,DMF被证明不会致突变,也不具有致癌性。近年来,人们在人体内DMF的代谢过程中对反应性中间体(大概是异氰酸甲酯)的形成提出了极大的兴趣。我们报告了在聚丙烯纤维行业中暴露于DMF的工人的血液样本中,血红蛋白(Hb)的N-甲基氨基甲酰化缬氨酸的形成。N-甲基氨基甲酰化的Hb是通过MIC与Hb反应形成的。为此目的,通过改良的埃德曼降解来监测血红蛋白加合物,该降解涉及以3-甲基-5-异丙基乙内酰脲(MIH)形式释放N末端缬氨酸加合物。为了对该方法进行内部标准化,使用了3-乙基-5-异丙基乙内酰脲(EIH)。MIH和EIH的分离和分析通过气相色谱和电子碰撞电离质谱(GC / EI-MS)进行。从接触者的血液样本中量化出MIH形式的Hb加合物,其浓度为26.1至412