Fig. 9

Axon tracing in brainstem tracts. Twenty-eight days post-SCI, rats were injected with BDA in the red nucleus and reticular formation and harvested 21 days after injection. Transverse sections displayed are rostral to the injury site (a), caudal in an uninjured rat, Control, Systemic IL-10, Local IL-10, MCMs, and MCMs+IL-10 (c). The percentage of axons that passed through to the caudal sections was calculated (b). The BDA injected rats had an average of 977 ± 93 axons labeled rostral to the injury. Uninjured rats had a significantly higher number of axons extending through to the caudal sections compared to all groups except the MCMs+IL-10 group. The rats treated with MCMs+IL-10 had a significantly higher percentage of labeled axons caudal to the injury, 35.92 ± 6.559%, when compared to Controls 15.81 ± 3.081% and Local IL-10 17.50 ± 3.804%. Red represents BDA labeled axons; blue represents DAPI; *P < 0.05 (Tukey’s Test); error bars represent ± SEM; n = 4 per group; scale bar = 500 μm