Test Cytotoxicity Of Cadmium And Formaldehyde By Using Mouse Embryo Fibroblasts Culture In Vitro

Objectives: To set up the methods of mouse embryo fibroblasts culture in vitro and to evaluate the toxicity of xenobiotics such as chloride cadmium and formaldehyde by using these methods.Methods: First, embryos are gotten by aseptic surgery from the mouse which had been pregnant for 12~16 days, then the embryo fibroblasts are cultured by using two methods. One method is to culture after digesting the tissues via 0.25% trypsin; the other is using little tissues directly. After conducting primary culture, we subculture the fibroblasts and get the purified fibroblasts. At last, we detect the cytotoxicity (MTT colorimetric assay) and genotoxicity (micronucleus test in vitro) of chloride cadmium and formaldehyde by means of the fibroblasts culture.Results: The experiment on primary culture and subculture in the mouse embryo fibroblasts was conducted successfully. The methods for culturing the mouse embryo's fibroblasts were confirmed and the cell growth curve was drawn. After the third generation cells were exposed to chloride cadmium or formaldehyde for 24 h, it showed that the half interdictory concentration (IC50) were 20.51 μ mol/L and 4.54 μ g/L, the linear regressionequations of common logarithm of dose and probit were 7=7.823?2.209X and Y =7.563 ?0.918X, and the linear correlation coefficients were-0.972, -0.994. When the cells exposed to chloride cadmium and formaldehyde for 24 h, the micronucleus test in vitro indicated that the two xenobiotics may increase the rate of micronucleus cells at the doses that not reduced the proliferation of the cells.Conclusions: Two methods (to culture after digesting the tissues by 0.25% trypsin or to culture little tissues directly) gain good effects on the mouse embryo flbroblasts culture. The former method is better than the latter. Using 0.125% trypsin is better than 0.05% trypsin/0.02% EDTA in the experiment of subculture. The flbroblasts were purified and those growth conditions were good when cells were subcultured to the third generation. The flbroblasts were exposed to chloride cadmium and formaldehyde in vitro, which can reduce the proliferation of the mouse embryo flbroblasts and lead to genotoxicity. The process of the experiments is reliable and repeatable. The methods can be applied to evaluate the toxicity of xenobiotics in vitro.