FIG. 10.

Axon tracing in a chronic delayed graft cat (CHRONIC-3) from a slice at approximately the dorsal-ventral midline of the spinal cord. The rostral end of the lesion site, ∼1 mm from the edge of the lesioned tissue, was injected with micro-ruby tracer (3000MW, D7162) and the caudal end was injected with micro-emerald (3000MW, D7156). All images are from horizontal sections near the center of the spinal cord. Fluorescent images are from sections adjacent to the corresponding Nissl-myelin- stained sections. Axons travel to the lesion edge but stop before entering or crossing the lesion. There was no evidence of emerald-stained axons in the rostral segment or of ruby-stained axons in the caudal segment. Sections immediately adjacent (dorsal and ventral) were also negative of any indication of growth through the lesion. In addition, no evidence of crossing was visible in sections rostral and caudal to the ones presented. Color image is available online at www.liebertpub.com/neu