Cadmium is a well recognized carcinogenic, cytotoxic and mutagenic transition
metal. Recent evidence suggests that the
proteins participating in the DNA repair systems, especially in excision and mismatch repair (MMR), are sensitive targets of
cadmium toxicity.
Microsatellite instability (MSI) is regarded as one of the phenotypes of defective
DNA MMR and, consequently, as a marker of high risk for
cancer. The purpose of this work is to determine whether
cadmium, in the form of
cadmium chloride (CdCl(2)), may induce microsatellite mutations in murine testes. For this study, 2-month-old male ICR-CD1 mice were treated by a single
subcutaneous injection of 1, 2 and 3 mg CdCl(2)/kg
body weight and killed after 35 days. A panel of six microsatellite markers, previously reported as being the most sensitive in detecting MSI in murine tumours, was used in this study. The results show that CdCl(2) in the doses of 2 and 3 mg/kg induced a decrease in the testis weight and severe histopathologic changes with complete disorganization of testicular structure and evidences of severe
necrosis. In addition, the animals exposed to the lowest CdCl(2) dose presented MSI in the testis. The results indicate the existence of MSI in at least two nuclear loci suggesting putative genotoxic effects induced by
cadmium.