(A) Glucagon secretion from the αTC1-6 cells and insulin secreton from INS-1 832/13 cells upon inhibition of the 2-oxoglutarate transporter with 10 mM phenylsuccinate. (B) Glucose-evoked alterations in shuttle intermediates in αTC1-6 and INS-1 832/13 cells treated with 10 mM phenylsuccinate. Data is expressed as means normalized to levels at 1 mM glucose (αTC1-6) and 2.8 mM glucose (INS-1 832/13) ± SEM for n=12 (1 mM and 16.7 mM glucose, αTC1-6), n=4 (16.7 mM glucose + 10 mM phenylsuccinate, αTC1-6), and n=8 (INS-1 832/13). Statistical significance was assessed using ANOVA followed by Newman-Keuls multiple comparison test post hoc, baseline vs 16.7 mM glucose *p<0.05, ***p<0.001, 16.7 mM glucose vs 16.7 mM glucose + phenylsuccinate, #p<0.05, ##p<0.01.