Fig. 4

Surgery impaired spine structural plasticity and decreased the activity of Rac1 signaling pathways during learning. a Dorsal hippocampal profile image of Golgi staining. b Representative tracing images of dorsal hippocampal CA1 pyramidal neurons on postoperative day 14. Sholl analysis of apical and basal dendrites of CA1 pyramidal neurons from rats c, d without behavioral training (home cage) and e, f with behavioral training (behavior, n = 24 neurons from 4 rats per group). g Total number of dendrites and h total dendritic lengths of traced images of dorsal hippocampal CA1 pyramidal neurons were analyzed using FIJI software (n = 24 neurons from 4 rats per group). i Representative images of the secondary branch of apical dendrites of CA1 pyramidal neurons in the dHPC on postoperative day 14 captured with a 100 × objective. Quantitation of the total spine, mushroom-shaped spine, thin-shaped spine, filopodia-shaped spine, and stubby-shaped spine densities in rats j without behavioral training and k with behavioral training (n = 24 neurons from 4 rats per group). l Representative immunoblots and m densitometry analysis of Rac1-GTP (active) and total Rac1 proteins levels in the dHPC on postoperative day 14 (n = 6 rats per group). n Representative confocal images of immunohistochemical staining for Rac1-GTP⁺ cells (green) in the dHPC captured with a 10 × objective. o Representative immunoblots and densitometry analysis of p phospho-Cofilin, Cofilin, and q Arp3 proteins in the dHPC on postoperative day 14 (n = 6 rats per group). Control-H control-home cage, Surgery-H surgery-home cage, Control-B control-behavior, Surgery-B surgery-behavior. Data are presented as means ± SEM and statistical analyzed by a Student’s t test (c, d, e, f, j, and k), a one-way ANOVA followed by a Tukey’s test (g, h, m, p, and q). *p < 0.05, **p < 0.01, and ***p < 0.001 compared with Control