Fig. 4

Whole-cell patch-clamp recordings in mouse primary trophoblasts: a Representative time trace of membrane current in mouse primary trophoblasts at 14 days post-fertilization. Magnesium-inhibitable current (MIC) was observed (n = 6) and inhibited by 100 μM 2-APB. The outwardly rectifying current–voltage relationship is shown on the right. Data suggest that currents were derived from TRPM7 homomer. b Representative time trace of membrane current at 18 days post-fertilization, after initiation of fetal bone mineralization. The result indicated that 2-APB activated the membrane current in a dose-dependent manner (n = 7), which has been shown for TRPM6/TRPM7 heteromer in heterologous expression systems. These data suggest that currents were derived from TRPM6/TRPM7 heteromer. c Statistical analysis of the dose dependency of 2-APB at +110 mV. The decrease at 14 days and the increase at 18 days were statistically significant (**p = 0.025, n = 7; *p = 0.047, n = 5, one-way ANOVA with Bonferroni post hoc test). Red and black dots in the traces indicate the point at which I–V curves were generated