Fig. 5.

Representative current traces showing progressive attenuation of peak glutamate-evoked currents by 20 μmMK-801 present only in agonist solution. Recordings were made in the continuous presence of 50 μm glycine from a cell transfected with NR1A/NR2A (A) or NR1A/NR2B (B). A₀,B₀, Representative control responses to 20 msec application of 1 mm glutamate alone.A_1–6,B_1–6, Successive current responses to simultaneous application of 1 mm glutamate and 20 μm MK-801 for 20 msec at 20 sec intervals.Insets show selected traces on an expanded time scale, along with the open tip recording to indicate speed of solution exchange in these experiments. Extracellular solution contained 0.2 mm calcium.