Fig. 4. Intracellular amino acid contents, amino acid uptake (positive) or export (negative) measured in C₂C₁₂ myotubes cultivated in the absence of glutamine (no addition and no addition plus glutamine synthase inhibitor) for 48 hours. Fig.s refer to the following measurements: (Above) intracellular content of amino acids. (below) Uptake (positive) or export (negative) of amino acids in cells; (A) L-glutamine, L-glutamate and L-alanine; (B) L-aspartate, L-asparagine, and L-ornithine. The experimental groups are: (0 mM) no glutamine addition in the medium; (0 mM with glutamine synthase inhibitor) no glutamine addition in the medium with the glutamine synthase inhibitor (L-methionine sulfoximine - MSO at 0.1 mM). Results are presented as mean ± standard error and were analyzed using one-way ANOVA and Tukey post-test. (^#p<0.05; ^##p<0.01) compared with 2 mM glutamine.