The in vivo nitrosation capacity of third-instar larvae of @entity238 was assessed using the wing somatic mutation and recombination test (SMART). Larvate derived from two different crosses, the standard cross (ST) and the high bioactivation cross (HB) both involving the recessive wing cell markers multiple wing hairs (mwh) and flare (flr3), were used. The HB cross is characterised by an increased @entity70366 -dependent bioactivation capacity for promutagens and procarcinogens. The larvae were treated either with @entity54149 , @entity11495 or its combination. @entity7045 was used as a positive control. The wings of the resulting flies were analysed for the occurrence of mutant spots produced by various types of mutational events or by mitotic recombination. @entity54149 is negative in the ST and the HB cross, whereas @entity11495 is weakly genotoxic in both crosses. However, the combination of both compounds produces highly increased frequencies of mutations and recombinations predominantly in the HB cross. The genotoxic effects produced by the combined treatments were considerably increased when mashed @entity415 or an agar- @entity375 medium were used for the treatment instead of the standard instant medium. Treatment of larvae with the mixture resulting from the in vitro reaction of nitrosation precursors also resulted in high frequencies of induced spots comparable to those recorded with the potent genotoxin @entity7045 . Further experiments showed that the genotoxic effect resulting from the in vivo exposure to nitrosation precursors can be reduced by co-treatment with @entity12919 , a known nitrosation inhibitor. The present study demonstrates that the wing spot test is well suited for the determination of genotoxicity produced by in vivo nitrosation processes and for the study of their modulation by individual compounds or dietary complex mixtures.

Analysis of the in vivo nitrosation capacity of the larvae used in the wing somatic mutation and recombination test of XXXX .

@entity7045 :: ('CHEBI:50102', 'Chemical') :: ['N-nitrosomethylurea', 'N-Nitrosomethylurea'] @entity54149 :: ('MESH:C002352', 'Chemical') :: ['methyl urea', 'Methyl urea'] @entity12919 :: ('MESH:D002392', 'Chemical') :: ['catechin'] @entity415 :: ('4113', 'Species') :: ['potatoes'] @entity11495 :: ('MESH:D012977', 'Chemical') :: ['sodium nitrite'] @entity375 :: ('4932', 'Species') :: ['yeast'] @entity238 :: ('7227', 'Species') :: ['Drosophila melanogaster'] @entity70366 :: ('35635(Tax:7227)', 'Gene') :: ['cytochrome P450']
@entity238 :: (7227,Species) :: ['Drosophila melanogaster']
