title: Increase of substance P-like immunoreactivity in the peripheral nerve of the axolotl after injury.
abstract: That substance P may be a neurotrophic factor in urodele limb regeneration was investigated in the axolotl (Ambystoma mexicanum). Two weeks after section of the peripheral nerves to the forelimb, there was a marked increase in substance P-like immunoreactivity (IR) content of the nerves proximal to the lesion. A smaller increase occurred as early as 3 days after section of nerves innervating a regrowing limb bud (blastema), and substance P-IR fibres were observed by immunocytochemistry to innervate blastema tissue. As substance P-IR by applying capsaicin to peripheral nerve--capsaicin had no effect on substance P-IR in either intact or injured axolotl nerves. Substance P fulfills a number of criteria of a trophic substance in axolotl limb regrowth.
mesh_terms: D000558:Ambystoma mexicanum; D000818:Animals; D005552:Forelimb / Q000294:innervation* / Q000502:physiology; D059348:Peripheral Nerve Injuries; D010525:Peripheral Nerves / Q000378:metabolism; D012038:Regeneration; D013373:Substance P / Q000276:immunology / Q000378:metabolism*
chemical_list: D013373:Substance P