Alamar Blue was purchased from Invitrogen (Grand Island, NY,USA). GLP-1 (7–36) amide rabbit polyclonal primary antibody was produced in-house at Queen’s University Belfast and validated in two ways; (1) Using a fully-optimised in-house radioimmunoassay with no cross-reactivity for glucagon or GIP (sensitivity= 59 ± 26.8 pM, r2 = 0.99), (2) Assessment of
immunofluorescence from non-GLP-1 secreting MDBK cell line.