Abstract:

Abstract:Objective To explore the mechanisms of DNA damage in rat H9c2 cells in vitro induced by different concentrations of cadmium chloride (CdCl2).Methods SCGE method was used to detect the DNA damage in rat H9c2 cells after exposed to 0,5,10,30,50 and 80 μmol?L-1 CdCl2 for 6,12 and 24 h.Western blotting was applied to observe the poly ADP-ribose polymerase (PARP) activity after 24 h exposure.Cytochrome-C (Cyt-C) and apoptosis inducing factor (AIF) expressions were measured by immunocytochemical method.Results With the increasing of CdCl2 concentration and exposure time,the DNA damage levels and rates of rat myocytes in 10,30,50 and 80  μmol?L-1 dose groups were increased after treated for 12 and 24 h.There were significant differences between various groups (P<0.05 or P<0.001).After treatment of CdCl2 for 24 h,the significant PARP cleavage fragment of 89 000 was found in 30,50 and 80  μmol/L dose groups.With the increasing of CdCl2 concentration,the Cyt-C and AIF protein expressions were significantly increased,there were significant differences between various groups (P<0.05 or P<0.001).Conclusion The toxic mechanisms induced by CdCl2 in rat H9c2 cells may be related to inducing the DNA damage and affecting the expressions of PARP,Cyt-C and AIF.There exists dose-dependent relationship.

Key words: cadmium chloride;cytotoxicity;poly ADP-ribose polymerase;cytochrome-c;apoptosis inducing factor