M. Katoh et al., MUTATIONS INDUCED IN MALE GERM-CELLS AFTER TREATMENT OF TRANSGENIC MICE WITH ETHYLNITROSOUREA, Mutation research. Genetic toxicology and environmental mutagenesis, 388(2-3), 1997, pp. 229-237
The present study was undertaken to clarify whether the transgenic mou
se mutagenesis assay system can be used instead of dominant lethals or
specific locus test after treatment of male germ cells in mouse with
ethylnitrosourea (ENU). Male Big Blue(TM) transgenic mice (BE) carryin
g a lacI tarpet gene were given a single intraperitoneal injection of
150 mg/kg ENU. Vasa deferential sperm, caudal epididymal sperm or whol
e testes were assayed for mutation at 3, 14, 22 and 93 days after trea
tment with ENU. The average of background lacl(-) mutant frequencies w
as 2.05x10(-5). The MF observed in post spermatogonial stage after tre
atment with ENU were slightly increased over background. On the other
hand, ENU induced high MF in the spermatogonial stage. MF detected aft
er treatment of BE male germ cells with ENU were lower than those dete
cted in the mouse visible specific-locus mutations in previous reports
. Nevertheless, it is clear that this assay is a practical alternative
to the specific locus test for detecting mutations induced in spermat
ogonial stage.