Figure 2. Glutamate and glutamine concentrations in the retina. WT and xCT KO retinal homogenates were collected, and total concentrations of glutamate or glutamine (glutamate + glutamine) were measured using a luminescence assay. (A) Total retinal glutamate concentrations in 6-week, 3-month, 6-month, 9-month, and 12-month-old WT (blue) and xCT KO (red) mice. (B) Total retinal glutamine concentrations for 6-week, 3-month, 6-month, 9-month, and 12-month-old WT (blue) and xCT KO (red) mice. Values represent mean ± SEM (n = 6).