FIGURE 4:

Cellular calcium changes and glutamate sensitivity of βGlud1^−/− islets. Islets were isolated from control and βGlud1^−/− mice and kept in culture before experiments. (A) Cellular calcium levels were monitored in islets loaded with fura-2 and placed in KRBH with 2.8 mM glucose before stimulation with 22.8 mM glucose. (B) Insulin secretion was tested in islets over a 1-h incubation period at 2.8 mM (Basal) and 22.8 mM (Glc) glucose supplemented with 5 mM dimethyl glutamate (dmGlut) where indicated. Values are means ± SE of six independent mice for each group. **, p < 0.01 vs. basal of corresponding genotype; §§, p < 0.01 vs. control under corresponding stimulation condition; ##, p < 0.01 vs. 22.8 mM Glc of corresponding genotype.