R. Rodriguezarnaiz, GENOTOXIC ACTIVATION OF HYDRAZINE, 2 DIALKYLHYDRAZINES, THIOUREA AND ETHYLENE THIOUREA IN THE SOMATIC W W+ ASSAY OF DROSOPHILA-MELANOGASTER/, Mutation research. Genetic toxicology and environmental mutagenesis, 395(2-3), 1997, pp. 229-242
Genotoxic activation of hydrazine (HZ), two symmetrical dialkylhydrazi
nes, namely, 1,2dimethylhydrazine and 1,2-diethylhydrazine (SDMH and S
DEH), thiourea (TU) and ethylene thiourea (ETU) has been evaluated by
means of the w/w + somatic assay of Drosophila. Both low bioactivation
insecticide-susceptible (IS) and high biotransformation insecticide-r
esistant (IR) strains were used. The combined application of insectici
de-susceptible and insecticide-resistant strains should, in principle,
detect somatic cell recombinagens in the Drosophila melanogaster in v
ivo w/w + assay. The IS strain was more susceptible to toxicity induce
d by the test chemicals than the IR stocks. Its performance in the bio
transformation of the chemicals tested was rather poor. TU was inactiv
e in all strains. With the active compounds, spot frequencies increase
d approximately linearly with dose for each spot type. SDEH gave a str
ong positive result in all three female genotypes exposed. HZ, ETU and
SDMH were overall weakly positive in the IR strain Haag-79 (HG-R). In
terestingly, ETU was clearly positive in the IR Hikone-R (HK-R) strain
. A comparison of the recombinagenic potencies between the active and
the weakly positive compounds, and among strains, showed pronounced ge
notype-dependent differences between the low and the high bioactivatio
n strains. The ability of Drosophila to express several procarcinogens
in relation to insecticide-resistance after activation catalyzed by C
YP450 enzymes is discussed. (C) 1997 Elsevier Science B.V.