Figure 2

Electron micrographs of SSeCKS-IR in the lumbar spinal cord dorsal horn. (A) SSeCKS labeling in the dorsal horn of the spinal cord demonstrating the zone within lamina II outer in which the band of SSeCKS labeling (upper left of micrograph) is separated (dashed line) from the area of the dorsal horn lacking SSeCKS labeling (lower right of micrograph). (B) SSeCKS labeling of thinly myelinated fibers (arrows) located next to larger diameter, more heavily myelinated axons lacking SSeCKS labeling. (C) SSeCKS labeling of a bundle of unmyelinated fibers. (D) Enlargement of portion of (C) reveals labeling around the axonal plasma membrane (black arrow) of individual unmyelinated fibers, as well as labeling around vesicular structures (white arrow).