Objective: To explore the anti-oxidation effects of daidzein (DD)on rat's myocardial hypertrophy caused by isopropylarterenol (Iso). Method: The rat's myocardial hypertrophy model was formed by hypodermic injection of Iso 1 mg·kg-1)for days at back skin

DD (0.1

0.3 μmol·kg-1)

dimethylsulfoxide(DMSO) or normal saline(NS) were administrated in intragastric way from the second day for 14 days. After the last administration

12 hours after fasting blood and heart were collected The indexes of whole heart and left ventricle were calculated

superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px)activity and malondialdehyde (MDA) concentration in serum were measured. Result: It showed that the indexes of whole heart and left ventriclein Iso group were much bigger than control one

the activity of SOD and GSH-Px in serum was decreased

and the concentration of MDA in serum enhanced. However

DD improved these indexes. Conclusion: DD has a protection on rat's myocardial hypertrophy caused by Iso through enhancing the anti-oxidation activity of rats.