Figure 7.

Dependence of external calcium or BAPTA-AM of the changes in cytosolic Ca²⁺, Na⁺, ATP, and ATP/ADP ratio and OCR induced by 25 μm NMDA in neocortical neuronal cultures. A, E, Cytosolic Ca²⁺ measurements in fura-2-loaded neurons; B, F, cytosolic Na⁺ in SBFI-loaded neurons; C, G, cytosolic ATP measurement in GO-ATeam-transfected neurons; D, H, cytosolic ATP/ADP ratio in Perceval-transfected neurons. A–D, In the presence of Ca²⁺. E–H, In nominally Ca²⁺-free media. The results correspond to representative experiments. I, K, OCR response to 25 μm NMDA in wt and Aralar KO neurons incubated with Ca²⁺ and in presence or absence of 1 μm BAPTA-AM. Data are mean ± SEM; n = 4-9. J, Histogram represents the decrease (***p < 0.001, n = 9, unpaired t test) in NMDA-induced stimulation of respiration in wt neurons in the presence of BAPTA-AM. K, In Aralar-KO neurons, the decrease was not significant.