Figure 2.
Sodium entry via AMPA receptors mediate neuronal glucose uptake inhibition. A, Hexose uptake by neurons was measured before and after the addition of 20 μm AMPA. The top trace corresponds to simultaneous nonquantitative assessment of cytosolic calcium with the reciprocal dye Fura Red (n = 6 cells). B, Inhibition of hexose uptake elicited by AMPA alone (n = 24 cells, 7 exps.) in the presence of 20 μm CNQX (n = 9 cells, 2 exps.) in a buffer in which Na+ was equimolarly replaced by N-methyl-d-glucamine (n = 15 cells, 3 exps.) and in the presence of 10 mm EGTA (n = 22 cells, 4 exps.). C, Hexose uptake by a neuron was measured before and after the addition of 75 μm veratridine. The top trace represents the corresponding Fura Red signal. D, Inhibition of hexose uptake by veratridine (Vera) (6-NBDG; n = 18 cells, 4 exps.), 2 μm ionomycin (Iono) (2-NBDG; n = 17 cells, 3 exps.), and 40 mm KCl(2-NBDG; n = 28 cells, 6 exps.).