Fig. 5.

Insulin enhances glucose sensitivity of anaerobic glycolysis. Typical XF24 extra-cellular acidification (ECAR) traces reflecting the glycolytic behaviour of L6 myoblasts (panel A), human myoblasts (panel B), and human myotubes (panel C). Glucose (GLU) was added at times indicated by the dotted lines to cells incubated without (white symbols) and with 100 nM insulin (black symbols). The shown traces are representative for the respective skeletal muscle cells, and each data point represents an average ECAR ± SEM of 4–5 wells. All rates were normalised to the final basal ECAR measurement. The ECAR response was quantified by normalising the average value of the (first) 4 readings after glucose addition to the final reading before glucose addition (panel D). The responses shown are means ± SEM of 3 independent experiments. As indicated by the asterisks, all differences between cells without (white bars) and with 100 nM insulin (black bars) were statistically significant (P < 0.05).