Figure 1.
Schematic representation of memantine and NMDA receptor.
Figure 2.
Memantine increased the adhesion property in Fmr1-KO CGCs.
Comparison of CGCs adhesion. The values are mean ±SE from three independent experiments with five replicates in each experiment, *p<0.05, **p<0.01. OD: optical density.
Figure 3.
Memantine had little effect on CGCs migration.
A. Cultured CGCs. Scale bar, 100 µm. B. CGCs stained with Calcein AM dye in modified Boyden chamber migration assay. Scale bar, 100 µm. C. Comparison of CGCs migration. The values are mean ±SE from three independent experiments with five replicates in each experiment. AFU: arbitrary fluorescence units.
Figure 4.
Memantine restored dendritic spine to normal levels in Fmr1-KO CGCs.
A. Cultured CGCs were stained with Vybrant-DiI to outline the shape of dendritic spines. Arrows colored in white show the mushroom-shaped spines, while arrows colored in yellow show the thin-shaped spines, Scale bars, 10 µm. Histogram showed the density of mushroom-shaped spines (B), spine length (C) and cumulative frequency distribution of spine lengths (D) in WT CGCs, Fmr1-KO CGCs and Fmr1-KO CGCs treated with memantine. The data are the mean ± SE, *p<0.05, **p<0.01. n = 3.
Figure 5.
Memantine fully restored the intensity of excitatory synapses to a normal range in Fmr1-KO CGCs.
Representative photomicrographs of labeling of VGLUT1 (arrow) in WT CGCs, Fmr1-KO CGCs and Fmr1-KO CGCs treated with memantine. Red, VGLUT1; Blue, Hoechst, scale bars, 25 µm. The histogram shows quantification of puncta size using image analysis. WT, n = 23; Fmr1-KO, n = 25; Fmr1-KO+Memantine, n = 26. *p<0.05.
Figure 6.
Memantine stimulated the formation of total synapses in Fmr1-KO CGCs.
Representative photomicrographs of labeling of Syp (arrow) in WT CGCs, Fmr1-KO CGCs and Fmr1-KO CGCs treated with memantine. Green, Syp; Blue, Hoechst, scale bars, 25 µm. The histogram shows quantification of puncta size using image analysis. WT, n = 23; Fmr1-KO, n = 25; Fmr1-KO+Memantine, n = 26. **p<0.01.
Figure 7.
Memantine stimulated the formation of inhibitory synapses in Fmr1-KO CGCs.
Representative photomicrographs of labeling of VGAT (arrow) in WT CGCs, KO CGCs and KO CGCs treated with memantine. Green, VGAT; Blue, Hoechst, scale bars, 25 µm. The histogram shows quantification of puncta size using image analysis and ratio of excitatory synapses to inhibitory synapse. WT, n = 23; Fmr1-KO, n = 25; Fmr1-KO+Memantine, n = 25. *p<0.05, **p<0.01.