Figure 1

The effects of PCP, UBP, and CIQ on motor performance. (A) Wildtype mice and KO mice did not display significant differences in motor learning. WT, wildtype mice (n = 60); KO, GluN2D knockout mice (n = 55). (B) Ataxic effects of phencyclidine (PCP) at 3.0 mg/kg (n = 15 WT, n = 17 KO) and 5.0 mg/kg (n = 16 WT, n = 15 KO) in the rotarod test at 12 rpm. A significant effect of genotype was observed in the PCP-induced decrease in time at the two doses tested (p < 0.05 at both doses, dependence on genotype; Fisher’s exact test). Twenty-four to 72 h after PCP injection, the WT and KO mice were injected with saline. Motor performance was not affected by saline injection. Almost all of the mice showed maximal performance at 12 rpm (> 300 s), and the remaining mice showed normal performance (> 200 s). (C) Effect of UBP in the rotarod test at 0 rpm (n = 10 WT, n = 9 KO) and 6 rpm (n = 9 WT, n = 8 KO). The differences between WT and GluN2D KO mice in UBP141-induced motor impairment were significant at 0 and 6 rpm (p < 0.05 at both speeds, dependence on genotype; Fisher’s exact test). The vehicle injection did not affect motor performances in WT and KO mice (both genotypes: > 300 s at 12 rpm, n = 5; > 200 s at 12 rpm, n = 2; < 200 s at 12 rpm, n = 1). (D) Effect of CIQ in the rotarod test at 12 rpm (n = 8 WT, n = 15 KO). The difference between WT and GluN2D KO mice in CIQ-induced motor impairment was significant (p < 0.05, dependence on genotype; Fisher’s exact test). The vehicle injection did not affect motor performances in WT and KO mice (WT: > 300 s at 12 rpm, n = 5; > 200 s at 12 rpm, n = 2; KO: > 300 s at 12 rpm, n = 11; > 200 s at 12 rpm, n = 2).