Mechanical stimulation activates mTOR signaling via an ERK-independent mechanism.

<p>EDL muscles were held at optimal length (<i>Lo</i>) in an <i>ex-vivo</i> organ culture system and pre-incubated with 50 µM U0126 (U0126+) or the vehicle (U0126 –, DMSO) for 30 min. The muscles were then subjected to 15 or 90 min of intermittent 15% stretch or held static at <i>Lo</i> as a control condition. Muscles were collected at the end of the 15 or 90 min interval and subjected to western blot analysis for phosphorylated (P) and total ERK, p70, S6, and 4E-BP1. The total amount, and phospho:total ratios, of each protein were measured and then expressed relative to the values obtained in the time-matched vehicle control samples (U0126 –, Stretch –). All values are presented as the mean (n = 3−6 per group). *Significantly different from the drug-matched control group, †Significantly different from the stimulation-matched vehicle group, P≤0.05.