GLP-1-induced cAMP production is mediated via tmACs. Cyclic AMP was measured in INS-1E cells after incubation for 5 min in 2.5 mM glucose in the presence of 0.5 mM IBMX, with either vehicle control, 30 μM KH7, 50 μM 2′5′ ddAdo, 30 nM GLP-1, GLP-1 and KH7, or GLP-1 and 2′5′ ddAdo. 2 d before the assay, 2.5 × 105 cells were plated into each well. Values represent means ± SEM (n = 8). ANOVA statistical analyses were performed with the Newman-Keuls post-hoc test. ***, indicates P < 0.001; *, P < 0.05.