Abstract: AIM:To investigate the effects of Hype- ricum perforatum on ischemic injury in PC12 cells . METHODS:PC12 cells were treated with 20 mmol·L^-1 NaCN in combination with glucose deprivation .Assay of MTT and lactate dehydrogenase for cell survival , cytosolic creatine kinase (CK)measure , Flow cytometric detection of apoptotic cells and the mitochondral membrance poten- tial in PC12 cells .RESULTS:Hypericum perforatum , within the range of 10^-7 -10^-5mol·L^-1 significantly in- creased the optical density at 570nm tested by colorimetric MTT assay , antagonized LDH efflux , increased CK activi- ty .Hypericum perforatum also decreased NaCN in combi- nation with glucose deprivation-induced PC12 cells apop- totic rate and increased mitochondrial membrance potential in concentration-dependent manner.CONCLUSION: Hypericum perforatum can protect PC12 cells from isch- emic injury .The mechanism is related to antagonizing the loss of CK activity and MMP in PC12 cells .

Key words: Hypericum perforatum ;PC12 cells , ischemic injury ;mitochondrial membrance potential ;ap- optosis