48 gluhu e01

Terminal plasma measurements were completed by the Mouse Metabolic Phenotyping Center (MMPC) at The University of Cincinnati, Cincinnati, Ohio (www.uc.edu/labs/mmpc.html). Assays include leptin (#EZRL-83K, EMD Millipore, Billerica, MA), gastric inhibitory peptide (GIP) (#EZRMGIP-55K, EMD Millipore,) total GLP-1 (EZGLP1T, EMD Millipore), C-peptide (EZRMCP2-21K, EMD Millipore) and glucagon (#48-GLUHU-E01, Alpco, Salem, NH). In addition, insulin concentrations were determined using an Insulin ELISA (#90060, Crystal Chem INC., IL). All assays were performed according to the manufacturer’s specifications.

Blood sampling was performed by tail vein bleed from unanesthetized, unstarved mice and analyzed immediately for glucose concentration by the glucose oxidase method using a One Touch II (Lifescan) glucometer. For C-peptide I and II analyses, in the case of young animals, sera were pooled from several mice in order to reach the 200 μL required for immunoassay. For fasting glucagon and insulin analyses, sera were collected from mice starved for 5 h. ELISA kits for mouse C-peptide I, C-peptide II, pancreatic glucagon, and total insulin were purchased from Alpco Diagnostics (respectively #48-CP1MS-E01, #48-CP2MS-E01, #48-GLUHU-E01, #80-INSMS-E01) with the assays performed according to the manufacturer’s instructions.