Effect of orthovanadate on HCD57 viability and proliferation.

(A) HCD57 cells were cultured for 96 hours in the presence of EPO (lane A), in the absence of EPO (lane B) or in the absence of EPO and supplemented with different concentrations of orthovanadate (lanes C-F) as indicated. For each growth condition, 10 μg of genomic DNA were analyzed by agarose gel. (B) HCD57 cells were cultured in the presence of EPO (♦), in the absence of EPO (○), or in the absence of EPO and supplemented with 70 μmol/L orthovanadate over a period of 96 hours (▪). The number of viable cells was determined each day by trypan blue exclusion. Error bars indicate the standard error of 8 determinations. (C) HCD57 cells were cultured in the presence of EPO (♦) or in the absence of EPO but supplemented with 70 μmol/L orthovanadate. At 24 (□), 48 (▴), 72 (░) and 96 (○) hours, aliquots of cells were removed from the minus EPO/plus orthovanadate culture. Each culture was washed free of orthovanadate and placed in fresh EPO containing media. The number of viable cells was determined each day by trypan blue exclusion. Error bars indicate the standard error of 8 determinations.