Objective   To investigate the effect of daidzein on activity of glutathione peroxidase(GSH-Px)and content of malondialdehyde(MDA)in heat-stressed mice.

  Methods   Thirty mice were randomly divided into three groups: the control group, the heat-stressed group and the heat-stressed group supplemented with daidzein.The mice were examined in terms of changes of activity of GSH-Px and content of MDA in liver, spleen, kidney and serum after being heat-str essed under the condition of(45±1)℃ for twenty minutes.

  Results   Compared with the control group, the activity of GSH-Px in liver, spleen and kidney in heat-stressed group increased, and there was significant difference in the result of liver(P < 0.05).The activity of GSH-Px in the daidzein group increased significantly compared with the control(P < 0.05 or P < 0.01).The activity of liver and spleen in the daidzein group increased significantly compared with that in the heat-stressed group(P < 0.05).The contents of MDA in two heat-stressed groups both increased compared with that in the control group, and there were significant differences in the result of liver and serum(P < 0.05).The MDA content in daidzein group was slightly less than that in heat-stressed group, but no statistical sig nificance(P > 0.05)was found.

  Conclusion   Daidzein can increase the activity of antioxidation in heat-stressed mice.