Effect of glucose and pancreatic hormone levels on AICAR-mediated AMPK activation in primary hepatocytes. Mouse primary hepatocytes were preincubated for 1 h under various culture conditions, including 5 mm glucose (G5), 5 mm glucose plus 100 nm insulin, or 5 mm glucose plus 100 nm glucagon (A) and 10 mm lactate and 1 mm pyruvate without glucose (L/P) plus 10 nm glucagon, 5 mm glucose (G5), or 25 mm glucose (G25) plus 100 nm insulin (B), and then various concentrations of AICAR (0, 50, 75, 100, or 200 μm) were added to the medium. After 8 h, cells were harvested for Western blot analysis. Immunoblots from hepatocyte lysates were performed using the indicated antibodies. The bottom panels represent the P-Thr172-AMPKα/AMPKα ratio from the quantification of immunoblot images. Results are representative of three independent experiments. Data are presented as the means ± S.D. (error bars). **, p < 0.01; ***, p < 0.001 compared with G5 or G25 conditions. Hatched bars indicate an increase in the P-Thr172-AMPKα/AMPKα ratio in hepatocytes incubated in L/P relative to those incubated in G5 or G25.