Fig. 8.
(A) Shown are two-electrode voltage-clamp recordings illustrating the rate of block by MK-801 of GluN1/GluN2D receptors containing point mutations in the GluN2D pre-M1 helix. Currents were activated by 100 μM glutamate and 30 μM glycine at a holding potential of −60 mV followed by coapplication of 200 nM (+)-MK-801. Traces were normalized to the glutamate/glycine current. (B) Open probability (Popen) of GluN2D point mutations, calculated as the reciprocal of the time constant of onset of MK-801 block (τMK-801 block) and normalized to the values for GluN2D, are shown. Bars represent mean ± S.E.M. for 3–10 oocytes.