227-LB: GLP-1 Activation of HCN Channels Increases Glucose-Stimulated β- and δ- Cell Ca2+ Oscillation Frequency

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels control human β-cell insulin secretion. Here, we examined if HCN channels impact glucagon-like-peptide 1 (GLP-1) receptor modulation of islet Ca2+ handling. We found that Liraglutide (100nM LIRA), a GLP-1 analog, increased mouse β-cell Ca2+ oscillation frequency and cAMP levels in high (11 mM) but not low glucose. Similarly, a subset of human β-cells (65%) show LIRA-induced elevations in Ca2+ oscillation frequency (by 70%, P Disclosure K. E. Zaborska: None. K. L. Jordan: None. P. Dadi: None. M. Dickerson: None. S. M. Graff: None. D. Jacobson: None.