Yoda K, Sakiyama S, Fujimura S
Chem Biol Interact. 1982 Jul 15;41(1):49-59. doi: 10.1016/0009-2797(82)90016-3.
Reactivity of N-ethyl-N'-nitro-N-nitrosoguanidine (ENNG) was studied in comparison with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). The radioactivity of [guanidino-14C]-ENNG was incorporated only into the protein fraction and that of [ethyl-14C]ENNG was incorporated into DNA, RNA and protein fractions in ascites hepatoma AH7974 cells, as were those of [guanidino-14C]- and [methyl-14C]MNNG, respectively. The amounts of the binding of ENNG were less than those of MNNG, especially in the corporation of the ethyl moiety of ENNG into nucleic acid fractions. In a non-cellular system, the radioactivity of [guanidino-14C]ENNG was incorporated into proteins, preferentially into basic proteins such as cytochrome c, but was not incorporated into nucleic acids. This behavior is similar to that of [guanidino-14C]MNNG, while the amount of binding of the former was about half of that of the latter. The radioactivity of [ethyl-14C]ENNG was also incorporated into basic proteins to almost the same extent as that of [methyl-14C]MNNG. However, the binding of the ethyl moiety of ENNG to nucleic acids was much lower than that of the methyl moiety of MNNG. Horse heart cytochrome c, bovine pancreatic RNase A and regenerating rat liver chromatin had altered their biological activities to various degrees after modification by ENNG or MNNG.
对N-乙基-N'-硝基-N-亚硝基胍（ENNG）的反应活性与N-甲基-N'-硝基-N-亚硝基胍（MNNG）进行了比较研究。在腹水肝癌AH7974细胞中，[胍基-14C]-ENNG的放射性仅掺入蛋白质部分，而[乙基-14C]ENNG的放射性分别掺入DNA、RNA和蛋白质部分，[胍基-14C]-和[甲基-14C]MNNG也是如此。ENNG的结合量低于MNNG，尤其是ENNG的乙基部分掺入核酸部分的情况。在无细胞体系中，[胍基-14C]ENNG的放射性掺入蛋白质中，优先掺入细胞色素c等碱性蛋白质中，但不掺入核酸中。这种行为与[胍基-14C]MNNG相似，而前者的结合量约为后者的一半。[乙基-14C]ENNG的放射性也以与[甲基-14C]MNNG几乎相同的程度掺入碱性蛋白质中。然而，ENNG的乙基部分与核酸的结合远低于MNNG的甲基部分。马心脏细胞色素c、牛胰核糖核酸酶A和再生大鼠肝脏染色质在经ENNG或MNNG修饰后，其生物活性都有不同程度的改变。
