<p><b>A</b>) Phosphorylation of LKB1 Ser428 was not affected by OA-NO<sub>2</sub> in BAECs. Confluent BAECs were exposed to 2.5 µM OA-NO<sub>2</sub> for 16 h, and phosphorylated LKB1-Ser428 was detected by a phospho-specific antibody in western blots. The blot is a representative of three blots obtained from three independent experiments. <i>Lower panels</i>: summary data (<i>n</i> = 3). <b>B</b>) LKB1 is not required for AMPK activation by OA-NO<sub>2</sub>. Confluent LKB1-deficient Hela-S3 cells were exposed to 2.5 µM OA-NO<sub>2</sub> for 16 h, and then AMPK and ACC phosphorylation were assayed as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0031056#s4" target="_blank">Materials and Methods</a>. The blot is representative of three blots obtained from three independent experiments. <i>Lower panels</i>: summary data (*<i>p</i><0.05 <i>vs.</i> control; <i>n</i> = 3). <b>C</b>) LKB1 siRNA did not abolish OA-NO<sub>2</sub>-stimulated AMPK activation in HUVECs. HUVECs were incubated with LKB1-specific siRNA or control siRNA for 48 h and then treated with OA-NO<sub>2</sub> or vehicle for 16 h. After treatment, cell lysates were analyzed for LKB1 protein levels and AMPK phosphorylation at Thr172. <i>Lower panels</i>: summary data (*<i>p</i><0.05 <i>vs.</i> control; <i>n</i> = 3).</p
