Fig. 4

Effect of ammonium salts on the viability of Gln-starved Sp2/0-Ag14 cells does not depend on glutamine synthesis. a Ramos B cells were deprived of l-glutamine for 24 h in the presence or absence of methionine sulfoximine (MSO). Cell viability was then determined using the trypan blue assay. *p < 0.05 vs corresponding control cultured in the presence of Gln ŧ < 0.05 vs corresponding PBS control. b Sp2/0-Ag14 cells were deprived of glutamine for 3 h in the presence of MSO and of 5 mM ammonium salt/sodium salt or an equivalent volume of PBS. Gln (4 mM) was then added and culture was resumed for 24 h. Cell viability was determined by trypan blue exclusion. Gln-deprived, PBS-supplemented cultures in which MSO was omitted were used as controls. For both panels, cultures in which Gln was added at the start of the experiment were included as controls. *p < 0.05 vs corresponding sodium salt-supplemented control