To probe into the mechanism of c fos, c jun expression regulated by preconditioning, we observed protein kinase C (PKC) changes of c fos, c jun gene transcription in cultured cardiomyocytes affected by transient ischemic and medicine preconditioning mimicking ischemia reperfusion injury. Cultured rat cardiac myocytes were exposed to ischemia reperfusion mimicking solution after brief ischemic episodes or PMA, norepinephrine, adenosine preconditioning. Using Northern hybridization assay, we detected the gene transcription of c fos, c jun in cardiomyocytes. In mimicking ischemia the content of c fos, c jun mRNA increased significantly. Drug preconditioning induced cardiomyocyte c fos ,c jun expression in varing degrees. H 7 blocked this preconditioning effect. These results suggest that through activating PKC preconditioning induced c fos, c jun expression and PKC might play a central role in ischemic preconditioning.