Alternative Expression of XRCC1 Gene in Target Organs of Rats Exposed Subchronically to Cadmium

摘要

The research is to investigate the alternative expression of XRCC1 gene in target organs of rats exposed subchronically to cadmium (Cd),to understand the toxic effects of certain DNA repair genes in vivo.Based on our pre-established animal model of subchronic cadmium exposure,the abnormal expressions of XRCC1 gene in the liver,kidney,heart and lung of rats treated with CdCl2 at different concentration were detected by fluorescent quantitative polymerase chain reaction (FQ-PCR).The levels of XRCC1 protein were further confirmed by western blotting analysis.Compared to the corresponding controls,under the inner standard of TBP,the expression levels of XRCC1 mRNA were significantly decreased in all the measured liver and kidney in all Cd exposed rats with dose-dependent manner (P＜0.01).Among low-dose,mid-dose and high-dose groups of the rats exposed to Cd,FQ-PCR assay showed that the XRCC1 mRNA expressions were respectively 45％,32％,13％ of controls in the liver; 68％,31％,16％ of controls in the kidney; 42％,30％,15％ of controls in the heart; and 47％,28％,19％ of controls in the lung.The western blotting analysis further displayed that the tendency of XRCC1 protein level was consistent with XRCC1 mRNA expression,indicating the subchronic Cd exposure cart obviously regulate down the expression of XRCC1 gene in main inner organs of rats.The alternative expression of XRCC1 gene in rat's liver,kidney,heart and lung might be an important biomarker for toxic effects during long-term low level exposure to Cd in vivo.