Abnormal stimulation of insulin secretion by pyruvate from islets in vitro. Islets isolated from a DT mouse were isolated,
divided, and cultured for 48 h in the presence (+Dox) or absence (−Dox) of 5 μg/mL doxycycline. Batches of six size-matched
islets were incubated in Krebs buffer with 3 mmol/L glucose for 60 min and then transferred to various concentrations of glucose,
pyruvate, or lactate in Krebs buffer for 30 min. Secreted insulin is presented as a percentage of total insulin content of
islets. Data are presented as mean ± SEM (n = 3–6). Data for each induction state were analyzed by ANOVA with Dunnett multiple comparison test to compare each condition
with 3 mmol/L glucose *P < 0.05; **P < 0.01.