Figure 8
Comparison of the cytotoxicity of ammonium-supplemented media with conditioned medium from irradiated cells. Cells were grown in fresh culture medium provided with none (closed circles), respectively 2 and 4 mM NH4Cl or in CMX (8 Gy, 50 000 cells, 96 h). Dashed lines show the surviving cells with the cloning efficiency included (A). Parallel to cell countings, the concentrations of ammonia were determined in the culture media (B) as well as those of arginine, ornithine and citrulline (C). Vertical bars represent the maximum deviation in the ornithine cycle composition for the 2 and 4 mM NH4Cl media with respect to the control.
