(A) Glucose, (B) insulin, and (C) glucagon concentrations in WT mice fasted overnight and injected i.p. with alanine (0.325 g/kg). (D) Glucose, (E) insulin, and (F) glucagon concentrations in Gcgr:Glp1rβcell–/– mice fasted overnight and injected i.p. with alanine. (G) Glucose, (H) insulin, and (I) glucagon concentrations in fed WT mice injected i.p. with alanine. (J) Glucose, (K) insulin, and (L) glucagon concentrations in fed Gcgr:Glp1rβcell–/– mice injected i.p. with alanine. *P < 0.05 vs. PBS control; values are mean ± SEM. Statistical tests: Student’s paired t test (B, C, E, F, H, I, K, and L and iAUC in A, D, G, and J) and 2-way ANOVA (A, D, G, and J).