Substrate oxidation. Glucose, palmitate and acetate oxidation was determined by a 96 multi-well tracer technique as previous described [11]. Substrate oxidation was monitored by incubating myotubes with [1-14C]-palmitate or [14C(U)]-glucose or [1-14C]-acetate at indicated glucose, palmitate or acetate concentrations with subsequent capture of liberated 14CO2 for 4 h at 37 °C. Trapped radioactivity was determined on a Microbeta counter (PerkinElmer, Finland). Measurements of acid soluble metabolites (ASM) was performed as described by Skrede et al. [12].
Glucose uptake: Glucose uptake was measured by capturing 2-[1-14C]-deoxy-glucose as previously described [7] and [13].