Orlic et al1 treated mice (splenectomized two weeks ago) with granulocyte colony stimulating factor (G-CSF) and stem cell factor (SCF) for five days before acute myocardium infarction (AMI) and three days after AMI.They found that those treatments could repair infarcted hearts,improve heart performance and decrease mortality.However,from the clinical standpoint,the work of Orlic and his co-workers has an obvious limitation.The strategy of delivering agents before infarction is not practicable because the onset of infarction is unpredictable.Therefore,we delivered the agents after infarction to modify its effect on rats closer to clinical reality.