Induction of micronuclei by cadmium chloride in AO rats depends on age and sex

Cadmium (Cd) is one of the most toxic industrial and metal in the environment which may cause severe genotoxic effects. The aim of the work was an evaluation of genotoxic effects of CdCl2 in genetically pure Albino Oxford (AO) rats, depending on sex, age and dosage. Experimental animals were treated intraperitoneally with three different concentrations of CdCl2: 0.5, 1, and 2 mg/kg of CdCl2, while the control animals received equal volume of sterile phosphate buffered saline. The individuals of both sexes were treated at the age of 3, 6 and 12 month. Frequency of micronuclei formation was evaluated in polychromatic erythrocytes (PCEs), 24h hours after the treatment. The results showed that CdCl2 caused a concentration-dependent increase of micronucleus frequency. The most significant differences were found between ages of 3/12 and 6/12 months at 0.5 and 1.0 mg CdCl2 concentrations. Namely, 3 month old males had higher frequency of MNi in comparison to 12 month old males, whereas in females it was the opposite. Likewise, 6 months old males exbibited greater sensistivity to CdCl2 in comparison to 12 month old rats, and in the females it was the opposite. Sex differences were further confirmed as slightly stronger genotoxic effects in 12 months old females treated with 0.5 and 1 mg/kg of CdCl2. Therefore, the genotoxic effects of cadmium in AO rats depend on concentration, age and sex.