FIGURE 5.
ATGL knockdown in INS832/13 cells reduces fuel-induced insulin secretion. A, insulin release was measured in mock, scrATGL, and shATGL cells incubated as indicated for 45 min at 1 or 10 mm glucose with 0.5% d-BSA in the presence or absence of 0.25 mm palmitate (Pal), 10 nm GLP-1, 35 mm KCl, or 5 mm glutamine plus 5 mm leucine. B, effect of ATGL knockdown on the KATP-independent/amplification pathway(s) of insulin secretion was determined in cells incubated at 1 or 10 mm glucose (G) in the presence or absence of 35 mm KCl with or without 0.25 mm diazoxide (Dz). C shows the differences in insulin release between 1 and 10 mm glucose from data shown in B. Means ± S.E. are of 9–15 separate determinations from 3 to 5 independent experiments. *, p < 0.05; ***, p < 0.001 versus scrambled ATGL for the same incubation condition; one way-ANOVA, Bonferroni post hoc test.