Figure 5.

Glutamate induces a pH-mediated decrease of oxygen consumption rate. Glycolysis was inhibited using 2-DG (10 mm) to promote mitochondrial activity, and glucose (5 mm) and pyruvate (5 mm) were given as substrates. a, Time course of oxygen consumption rate in intact astrocytes in the absence and presence of glutamate (top; n = 7). When glutamate-induced cellular acidification was compensated by coadministration of TREA (20 mm), glutamate no longer significantly decreased oxygen consumption rate (bottom; n = 6). As a control, mitochondrial respiration was inhibited using oligomycin (5 μm) and then increased using FCCP (2 μm) at the end of each experiment. b, Average data of glutamate-induced decrease in oxygen consumption rate with increasing concentrations of TREA. Data were normalized to oxygen consumption rate before glutamate addition for each experiment (n = 42).