Fig. 7.

Effects of spermine and ifenprodil at GluN1/GluN2 receptors containing wild-type or chimeric GluN2B and GluN2A subunits. Schematics of the chimeric GluN2B and GluN2A constructs are shown in the figure. R1, R2, L1, and L2 indicate lobes of the R domains and LBDs, respectively. Linker (↓) indicates the linker region between the R domains and the LBDs. Spermine stimulation and ifenprodil inhibition were measured at GluN1/GluN2 receptors containing wild-type or chimeric GluN2 subunits using 100 μM spermine and various concentrations of ifenprodil in oocytes voltage-clamped at −20 mV. The EC₅₀ values for glutamic acid and glycine were determined from currents measured over a range of concentrations of glutamic acid and glycine. Values are means from at least five oocytes. Statistical analysis was performed using one-way analysis of variance with a Tukey-Kramer post hoc test. **, p < 0.01 versus values obtained from GluN1/GluN2B receptors.