Mutagenic effect of dimethylnitrosourea in male mice: induction of dominant lethal mutations and chromosome aberrations in germ cells; genotype influence on the clastogenic effect in bone marrow cells.

摘要

Male mice of an F1 strain cross, aged 8 weeks, were injected intravenously with 200 mg nitrosomethylurea/kg body weight, The males were mated with untreated, virgin females at weekly intervals for 6 weeks. Control matings were carried out with untreated males. Postimplantation embryo mortality was 19% for females mated to males 2 weeks after treatment vs. 5% for control matings. Chromosome aberrations were observed in the bone marrow cells of males 24 h after mutagen treatment. Nitrosomethylurea induced dominant lethal mutations in postmeiotic cells and spermatogonia, but not in spermatocytes. The effect of 200 mg nitrosomethylurea/kg body weight on the induction of chromosome aberrations in bone marrow cells of male mice of 8 strains was also studied. The percentage of aberrations ranged from 8.2% in CBA/Lac mice to 26.8% in TPS mice, values in untreated, control mice being close to zero.