Figure 2.

CTB labeling of muscle afferents in cervical spinal cord. Following bilateral injections of transganglionic neuronal tracer CTB into the extensor carpi radialis muscle groups, representative coronal sections of spinal cord cervical enlargement (segmental level C5) show CTB-labeled primary afferent terminations and motor pools in sham (A) and unilateral pyramidal tract lesion (C). The insets (a, a′, c, c′,) show magnified views of dorsal horn with Rexed's laminae indicated. Color-coded representations (heat maps) of the local density of CTB labeling for the group of sham controls (B, n = 6) and PTx (D, n = 5). Color scales plot sparse (blue) to dense (red) label (B, 0–0.55; D, 0–35; arbitrary units). Scale bars: A, C, insets, 500 μm; B, D, 650 μm.