Figure 3.

MSK1 regulates environmental enrichment-induced spine growth. A, Fluorescent dextran labeling of dendrites and spines in stratum radiatum of area CA1 in standard housing (top images) and enriched environment (bottom images) in wild-type (left) and MSK1 KD neurons (right). B, Spine density was significantly increased in wild-type mice (***p < 0.001) following environmental enrichment, but to a smaller extent in MSK1 KD (*p < 0.05), which showed increased basal spine density (⁺p = 0.044). Data reflect measurements on 12–27 dendrites from two to three mice for each condition. Scale bar, 10 μm. Error bars indicate SEM.