Figure 5.

Differences in gene expression are not explained by NR2 subunits or by steady-state Ca²⁺ levels. a, NMDA-induced [Ca²⁺]_i responses in NR1^−/− neurons transfected with NR1–1a, NR1–2a, and NR1–1a_Δ839–900 were all inhibited to a similar extent by ifenprodil. Mean ± SEM for at least three independent experiments. *p < 0.01, unpaired t test. b, NMDA-induced steady-state Ca²⁺ levels among NR1 subunits show no significant differences after 30 min (mean ± SEM fura-2 ratio for at least 14 neurons). C, Control; N, NMDA.