Representative isPLA images and average ratios ± SD of β1integrin/FAK (A, B), and β1integrin/pY397 (C, D) from muscles with no treatment (Control), and (EFS) (10Hz, 5sec) in the presence of 100μM L-NNA and 1μM MRS2500, without, or with 1μM PF-431396. **P<0.01, ***P<0.001, ****P<0.0001, ns P>0.05, n=3 for each treatment.