Fig. 2

The nanopattern surface improves Ca²⁺ responses to electric field stimulation. a Four-day-old myotubes were loaded with 5 μM Cal520-AM to detect changes in cytosolic Ca²⁺ concentration upon 1 min of electric field stimulation (bursts of 1 s at 10 Hz, every 10 s). Representative recordings of myotube responses on flat and striated surfaces (ANFS). The fluorescence intensity was expressed as F/F₀. b Cell responses to stimulations were classified based on the amplitude of the first peak: non-responders, amplitude < 0.5; responders, amplitude > 0.5. Bar charts represent the percentage of each category of responses on the two surfaces, flat and nanopattern (ANFS). Data were obtained from four independent experiments