mTOR is dispensable for collateral axonal sprouting following CNS injury in postnatal mice. A–D, Representative C5 coronal sections, enlarged midline (A′–D′) or Z1 (A″–D″) from sham and P7 pyramidotomy groups with vehicle or rapamycin treatment. BDA was injected into motor cortex 2 weeks before euthanasia. E, Quantifications of crossing axons counted in different regions normalized against the numbers of labeled CST axons (n = 7–9/group). Asterisk indicates significantly different to the “sham” group; p < 0.0001, two-way repeated-measures ANOVA followed by Bonferroni post-test. Error bars indicate SEM. Px, Pyramidotomy. Scale bar, 500 μm.