Abstract: ObjectiveTo study the effects of pervanadate(Per),the inhibitor of protein tyrosine phosphotases on the alterations of mito chondrial membrane potential(MMP)and the apoptosis of BET-2 cells induced by ionizing irradiation.MethodBET-2 cells were divided into Per-treated groups and non-Per groups and incubated after ionizing irradiation.The MMP and apoptosis were measured with FCM.ResultsAfter irradiation was given,the MMP of BET-2 cells was reduced in the early stage significantly,and the apoptosis appeared,and these changes had a dose-dependent pattern and a time-course fashion.Per potently enhanced the MMP of BET-2 cells and prevented irradiation-treated cells from apoptosis.ConclusionPer reversed the repression of mitochondrial membrane potential and suppress apoptosis induced by ionizing irradiation in the hematopoietic cells.