Figure 2From: The modulation of TRPM7 currents by nafamostat mesilate depends directly upon extracellular concentrations of divalent cationsNM completely and reversibly inhibits TRPM7 current in cultured mouse hippocampal neurons. A, top, experimental protocol showing voltage ramps (-100 to +100 mV) and applied low divalent cations. TRPM7 was elicited by lowing divalent cations from 2 mM Ca2+, 1 mM Mg2+ to indicated lower concentrations. Bottom, current trace examples of 0 Ca2+ and 0 Mg2+-induced TRPM7 current at the presence and absence of NM. Co-application of NM (200 μM) reversibly blocked TRPM7 evoked by zero divalent cations. n = 6. B, NM (200 μM) completely blocks TRPM7 evoked by 0.1 mM Ca2+ (and 0.1 mM Mg2+). Example current traces superimposed (left) and I-V curve (right). n = 8. C, concentration response of NM blockade of TRPM7 current, Left, currents trace examples. NM was acutely applied in the presence of 0.1 mM Ca2+ and 0.1 mM Mg2+. The onset time constrant of NM inhibition (200 μM) was 0.29 ± 0.04 s (n = 9) and the offset time constant was 1.07 ± 0.20 s (n = 9). Exponential fitting curves (red) were inserted with the trace (when NM is 200 μM). Right, concentration response curve of NM inhibition; IC50: 27 ± 6 μM; hill coefficient: 1.4; n = 6.Back to article page