Direct NMDAR activation causes membrane hyperpolarization in mice deficient in leptin receptor signaling.
A, representative cell-attached membrane potential recordings from β-cells isolated from C57BL/6J (WT) mice treated with leptin (top trace) or β-cells isolated from db/db mice treated with leptin (10 nm) followed by diazoxide (250 μm; bottom trace). B, group data showing the degree of membrane hyperpolarization in mV for β-cells isolated from C57BL/6J (WT, n = 9) or db/db (n = 7) mice for the indicated conditions. Gray and black circles indicate different animals. ***, p < 0.0001, unpaired Student's t test compared with WT leptin–treated group. C, as described for A except β-cells were treated with NMDA (50 μm). D, group data showing the degree of membrane hyperpolarization in mV for β-cells isolated from C57BL/6J (n = 9) or db/db (n = 9) mice following NMDA treatment. Error bars, S.E.