(a) Primary rat astrocytes were incubated in Basal, HYPO, or isoosmotic Low-Na media for 30 min. Levels of 5 intracellular amino acids were analyzed in cell lysates using an HPLC assay and normalized to protein content. Data are the mean values ± SE of 7–8 experiments. *p<0.05, ***p<0.001, vs. basal. Inset shows changes in glutamine levels on an expanded scale. (b) Effect of hypoosmotic medium on L-glutamate, L-glutamine, and taurine content was prevented by the VRAC inhibitor 20 μM DCPIB. Results are the means of 4 experiments. Inset shows changes in glutamine levels on an expanded scale.