Clevudine inhibited glucose-stimulated insulin secretion. Released insulin and cellular insulin content were measured using an enzymatic immunoassay after incubation with Krebs buffer containing 2.8 mM or 16.7 mM glucose for 15 min. Glucose-stimulated insulin secretion was impaired by clevudine incubation (A), as well as by inhibiting mitochondrial ATP synthase with oligomycin (B). Insulin release was normalized to the insulin content. Data presented are mean ± SEM. ** denotes p < 0.01.