STUDY ON RADIATION PROTECTION EFFECTS OF ZINC ON MICE MYELOID ELEMENT CULTURED IN VITRO

[Objective]To observe the protective effects and the possible mechanisms of zinc on γ-ray induced irradiation damages of mouse bone marrow(BM)cells cultured in vitro.[Methods]The BM cells were separated from mice and were suspended in RPMI1640 mediums. Zinc was added to the mediums,whose final concentrations in the mediums were 20?200?400?800 μmol/L respectively. Then the cells were irradiated by 60Coγ-ray of 5 Gγ. 16 hours later,the number of BM karyote and the contents of DNA of BM cells were measured. The damages of DNA and the rates of cell apoptosis were also examined by flow cytometry(FCM)and comet assay. [Results]After irradiation,compared with blank control group,the number of BM karyote and the contents of DNA decreased,the rates of cell apoptosis and damages of DNA increased. When Zn2+ was added to the cell cultures before irradiation,the rates of cell apoptosis and damages of DNA decreased,and the number of BM karyote and the contents of DNA increased. The dose response relation was observed when the concentrations range of zinc was 200-800 μmol/L.[Conclusions]Zinc may protect mice BM cells against radiation damages in vitro by protecting DNA and restraining cell apoptosis.