Inoue H, Fukunaga A, Okubo S
Mutat Res. 1981 Mar;88(3):281-90. doi: 10.1016/0165-1218(81)90039-2.
The standard sex-linked recessive lethal test was used to test whether NO2 induces lethal mutations in male germ cells of Drosophila in the presence or absence of alkylureas. Methylurea, ethylurea and NO2 alone did not enhance the mutation frequency significantly. However, highly significant enhancement in the mutation frequency was observed when adult flies were exposed to NO2 (150--280 ppm) for 3 h after ingestion of methylurea (0.1 M) or ethylurea (0.1 M) for 2 days. Oral administration of ethylnitrosourea and also of methylurea or ethylurea that had been exposed to NO2 in vitro were more effective in increasing the mutation frequency than methylurea or ethylurea combined in vivo with NO2. These results suggest that ingested alkylurea is converted in vivo by inhaled NO2 to highly mutagenic nitrosoalkylurea and/or other mutagens. No significant enhancement of the mutation frequency was observed when flies were fed on methylurea solution after they had been exposed to NO2.
采用标准的性连锁隐性致死试验，以检测在有或没有烷基脲存在的情况下，二氧化氮是否会在果蝇雄性生殖细胞中诱发致死性突变。单独的甲基脲、乙基脲和二氧化氮并未显著提高突变频率。然而，当成年果蝇在摄入甲基脲（0.1M）或乙基脲（0.1M）2天后，再暴露于二氧化氮（150 - 280ppm）3小时，观察到突变频率有高度显著的提高。口服乙基亚硝基脲以及体外暴露于二氧化氮的甲基脲或乙基脲，在增加突变频率方面比体内与二氧化氮联合使用的甲基脲或乙基脲更有效。这些结果表明，摄入的烷基脲在体内被吸入的二氧化氮转化为高致突变性的亚硝基烷基脲和/或其他诱变剂。当果蝇在暴露于二氧化氮后喂食甲基脲溶液时，未观察到突变频率有显著提高。
