Figure 3: Dynamic changes in intracellular calcium concentrations [Ca2+]i of a control neuron (A) and a ketamine-exposed neuron (C). Application of NMDA (50 μM) or glutamate (25 μM) caused an immediate elevation in intracellular free Ca2+ for both control (B) and ketamine-exposed (D) neurons. No NMDA-evoked [Ca2+]i rise was observed when the extracellular Ca2+ was chelated and, thus, unavailable for intracellular transport (50 μM NMDA + 200 μM EGTA in the perfusion buffer). A significant increase in intracellular free calcium [Ca2+]i was detected in ketamine-exposed neurons (D and E) compared to control neurons (B and E) after NMDA (50 μM) stimulation. Each condition was assessed at least in triplicate and experiments were repeated independently three times. Data are presented as means ± S.D.