Partial reduction of GSK3β activity increases axonal growth through the glial scar. (A) Representative images of dorsal column fibers traced with CT-B in sagittal sections following dorsal hemisection in WT or GSK3β(+/-) mice. r: rostral; c: caudal; d: dorsal; v: ventral. Dashed lines label the border of the glial scar. Arrowheads highlight axons regenerating rostrally to the SCI site. Scale bar: 50 μm. (B) Representative images of 5-HT-immunostained serotonergic axons (red) counterstained with DAPI (blue) observed caudal to the lesion site in sagittal spinal cord sections following a complete transection in WT or GSK3β(+/-) mice; (n = 5 to 6). Scale bar: 50 μm. (C) Number of CT-B + dorsal column axons able to enter the glial scar following dorsal hemisection (CT-B+) and of 5-HT-immunostained serotonergic axons observed caudal to the lesion site following a complete transection (5-HT+) in WT or GSK3β(+/-) mice. (D) Basso Mouse Scale (BMS) open field test following a complete spinal cord transection in WT and GSK3β(+/-) mice; (n = 6 to 7). All error bars are SEM. *P <0.05. Two-tailed Student’s t test. DAPI, 4′,6-diamidino-2-phenylindole; GSK3β, glycogen synthase kinase 3β; SCI, spinal cord injury; SEM, standard error of the mean; WT, wild type; 5-HT, 5-hydroxytryptamine.