Figure 1.
Effects of sciatic nerve defects on substance P expression in L5 dorsal root ganglia of rats (immunohistochemical staining, streptavidin-biotin complex, × 400).
Light microscopy showed that substance P-positive products (arrows) stained dark yellow or brown, mainly distributing in fibrous tissue.
(A) Substance P-positive products were dense and darkly stained in the dorsal root ganglion of normal rats at 7 days. No significant difference was found in staining or distribution of substance P-positive products between 14 (B) and 7 days (A) in the dorsal root ganglion of normal rats.
(C) Substance P-positive products stained darker in rats with sciatic nerve injury than in normal rats and expression was significantly increased at 7 days.
Expression of substance P was reduced and staining became lighter in rats with sciatic nerve injury at 14 days (D) compared with 7 days (C), but was still higher than in normal rats.
(E) Expression of substance P in rats with sciatic nerve injury was similar to that in normal rats at 28 days.