Palmitate-induced myotube loss could not be duplicated by the blockage of PI3K and p38 pathways. Myotubes were pretreated with 10 uM LY294002, or 10 uM SB203580 for 1 hour, followed by 0.4 mM palmitate for 24 hours. 0.1% DMSO as the control for inhibitor treatment, and BSA as the control for palmitate treatment. (A) Representative photographs taken under a phase contrast microscope; (B) The number of myotubes per photograph was counted after crystal violet staining. **p<0.01 vs. CTL. PA, palmitate; LY, LY294002; SB, SB203580.