Trans-generational radiation-induced chromosomal instability in the female enhances the action of chemical mutagens.
Genomic instability can be produced by ionising radiation, so-called radiation-induced genomic instability, and chemical mutagens. Radiation-induced genomic instability occurs in both germinal and somatic cells and also in the offspring of irradiated individuals, and it is characterised by genetic changes including chromosomal rearrangements. The majority of studies of trans-generational, radiation-induced genomic instability have been described in the male germ line, whereas the authors who have chosen the female as a model are scarce. The aim of this work is to find out the radiation-induced effects in the foetal offspring of X-ray-treated female rats and, at the same time, the possible impact of this radiation-induced genomic instability on the action of a chemical mutagen. In order to achieve both goals, the quantity and quality of chromosomal damage were analysed. In order to detect trans-generational genomic instability, a total of 4806 metaphases from foetal tissues from the foetal offspring of X-irradiated female rats (5Gy, acute dose) were analysed. The study's results showed that there is radiation-induced genomic instability: the number of aberrant metaphases and the breaks per total metaphases studied increased and were found to be statistically significant (p < or = 0.05), with regard to the control group. In order to identify how this trans-generational, radiation-induced chromosomal instability could influence the chromosomal behaviour of the offspring of irradiated rat females in front of a chemical agent (aphidicolin), a total of 2481 metaphases were studied. The observed results showed that there is an enhancement of the action of the chemical agent: chromosomal breaks per aberrant metaphases show significant differences (p < or = 0.05) in the X-ray- and aphidicolin-treated group as regards the aphidicolin-treated group. In conclusion, our findings indicate that there is trans-generational, radiation-induced chromosomal instability in the foetal cells from X-ray-treated female rats and that this RIGI enhances the chromosomal damage caused by the chemical agent aphidicolin.
Camats
Núria
N
Institut de Biotecnologia i Biomedicina (IBB), Universitat Autònoma de Barcelona, 08193 Barcelona, Spain.
García
Francisca
F
Parrilla
Juan José
JJ
Calaf
Joaquim
J
Martín
Miguel
M
Caldés
Montserrat Garcia
MG
D000818:Animals; D016590:Aphidicolin / Q000633:toxicity*; D043171:Chromosomal Instability / Q000528:radiation effects*; D002869:Chromosome Aberrations / Q000528:radiation effects; D005260:Female; D005333:Fetus / Q000187:drug effects*; D005854:Germ Cells / Q000187:drug effects* / Q000528:radiation effects*; D009153:Mutagens / Q000633:toxicity*; D051381:Rats; D017207:Rats, Sprague-Dawley
D009153:Mutagens; D016590:Aphidicolin