Effect of fingolimod treatment on PFC presynaptic calcium concentration as measured by fluorescent calcium indicators. Baseline levels of intracellular calcium did not significantly differ between genotype, as measured by fluo-4 and fluo-3 (WT SAL, n = 9; MUT SAL, n = 6). After treatment, fluo-4 measures showed significant increases in intracellular calcium in both WT (n = 9; ★★P = 0.001) and dysbindin-1 MUT (n = 6; ★★★P < 0.0001) mice. Both dyes indicate a near doubling of intracellular calcium for both genotypes after treatment with fingolimod. SAL, saline.