Fig 1. PEMF exposure of hBM-MSCs grown on TiO₂ variously interferes in the expression of voltage-gated calcium channels (VGCCs).

A) Current traces were elicited applying voltage pulses 100 ms long from –40 to +70 mV. The amplitude of the current recorded in Ba 108.8 mM (left traces) decreased after the application of nifedipine, (right traces), a specific blocker of L-type VGCC. B) Current-voltage relationships of the traces in A. C) Number of MSCs growing on TiO₂ and expressing VGCCs during osteogenesis without/with PEMF exposure. Data were normalized to the number of cells grown on glass and subjected to the same treatment. D) Normalized VGCC I_max value for the same population as in C. E) Number of cells grown on TiO₂ and exposed to PEMF normalized to the unstimulated sample and plotted in relation to the growing culture medium. F) Maximal current values of cell grown on TiO₂ and exposed to PEMF normalized to the unstimulated sample and plotted in relation to the growing culture medium. G) The expression of VGCC proteins carrying the currents as the one reported in panel A was confirmed by immunolocalization in MSCs grown on TiO₂ during osteogenesis (OM) and under PEMF stimulation (OM/PEMF+). No fluorescence was observed in hBM-MSCs grown in PM s a control (data not shown).