RÉSUMÉ
The paper covers investigation of cytogenetic activity of chiral mutagens and their specific effects on the plant cells chromosomes of soft winter wheat (Triticum aestivum L.). Comparative analysis of cytogenetic activity of chiral NEU: S(+)1-N-nitroso- 1-N-methyl-3-N-sec-buthylureas (S(+)NMsBU) and R(-)1-N-nitroso- 1N-methyl-3-Nsec-buthylureas (R(-)NMsBU) on winter wheat was performed. As it was shown by the frequency of chromosomal aberrations the S(+) stereoisomer was twice more active than R(-). In addition to typical anaphase aberrations (fragments, bridges, lagging chromosomes) the numerous mitosis pathologies were revealed - K-mitoses, hyperspiralization and despiralization of chromosomes, unequal allocation of chromosomes between the daughter nuclei, mass fragmentation, nondisjunction and chromosome adhesion, three-pole mitoses, etc. Neither of the mentioned pathologies was observed under the action of NEU and gamma-rays.
Sujet(s)
Noyau de la cellule/effets des médicaments et des substances chimiques , Aberrations des chromosomes/effets des médicaments et des substances chimiques , Chromosomes de plante/effets des médicaments et des substances chimiques , Mitose/effets des médicaments et des substances chimiques , Mutagènes/pharmacologie , Nitrosourées/pharmacologie , Triticum , Noyau de la cellule/génétique , Noyau de la cellule/effets des radiations , Noyau de la cellule/ultrastructure , Aberrations des chromosomes/effets des radiations , Chromosomes de plante/effets des radiations , Chromosomes de plante/ultrastructure , Rayons gamma , Mitose/effets des radiations , Mutagènes/synthèse chimique , Nitrosourées/synthèse chimique , Stéréoisomérie , Triticum/cytologie , Triticum/effets des médicaments et des substances chimiques , Triticum/génétique , Triticum/effets des radiationsRÉSUMÉ
Nitrosoalcoxyalkylamines are more efficient producers of nitrogen oxide in vivo than nitrosoalkylamines. Production of nitrogen oxide was monitored by EPR. The patterns of denitrosylation have been studied. The ability of the studied compounds to produce nitrogen oxide in vivo may be related to their carcinogenic and mutagenic action.
Sujet(s)
Cancérogènes/pharmacologie , Mutagènes/pharmacologie , Oxydes d'azote/métabolisme , Composés nitrosés/pharmacologie , Animaux , Pression sanguine/effets des médicaments et des substances chimiques , Citrates/pharmacologie , Spectroscopie de résonance de spin électronique , Composés du fer III/pharmacologie , Foie/composition chimique , Foie/effets des médicaments et des substances chimiques , Mâle , Souris , Oxydes d'azote/analyse , Nitrosation , RatsRÉSUMÉ
Raising total positive charge of a chemical mutagen does increase its local concentration in the area of biological target-DNA, and, as a consequence, causes increase in the rate of interaction of a mutagen with the target. Experimental evidence of this idea has been obtained in three test systems: the Ames test, Trp+ reversions in Escherichia coli WP2 and in the automated "SOS-chromotest" system with E. coli PQ 37 ("Labsystems", Finland).