FIG. 4.

Activation of transient receptor potential melastatin type 7 channel (TRPM7) in response to depletion of intracellular Mg²⁺ in mesenchymal stem cells. (A) Average TRPM7 currents in cells perfused with decreasing Mg²⁺ concentrations. Traces are mean + s.e.m. (n = 4–11 cells/concentration) extracted at +80 mV from 50 ms ramps spanning −100 mV to +100 mV applied every 2 s from a holding potential of 0 mV. (B) Current–voltage relationships (I/V) under experimental conditions as described above taken from representative cells at the peak current amplitude (600 s) for each Mg²⁺ concentration. (C) A dose–response analysis resulted in an IC₅₀ and Hill coefficient for Mg²⁺-induced inhibition of 0.130 mM and −1, respectively.