Neurotoxic damage evokes regenerative responses from adult rat sensory neurones.
When adult rats were pre-treated systemically with the excitotoxin, capsaicin, a subset of their dorsal root ganglion (DRG) sensory neurones responded as if they had been axotomised. Firstly, an increased proportion of capsaicin-sensitive DRG neurones (identified by using a cobalt stain) vigorously extended processes in vitro. Additionally, a subset of small dorsal root ganglion neurones expressed elevated levels of the growth-associated protein-43 (GAP-43) in situ. Both vigorous neuritogenesis and elevated GAP-43 levels are characteristics of neurones that are actively regenerating following mechanical damage. Although capsaicin-treated adult DRG neurones show these regenerative responses, their C-fibers fail to regenerate in vivo.
Winter
J
J
Sandoz Institute for Medical Research, London, UK.
Evison
C J
CJ
O'Brien
C
C
Benowitz
L
L
Lindsay
R M
RM
Mulderry
P
P
Woolf
C
C
D000818:Animals; D002211:Capsaicin / Q000494:pharmacology; D002478:Cells, Cultured; D019922:GAP-43 Protein; D005727:Ganglia, Spinal / Q000166:cytology / Q000187:drug effects; D008562:Membrane Glycoproteins / Q000378:metabolism; D009412:Nerve Fibers / Q000187:drug effects; D009416:Nerve Regeneration / Q000187:drug effects*; D009419:Nerve Tissue Proteins / Q000378:metabolism; D016501:Neurites / Q000187:drug effects; D009475:Neurons, Afferent / Q000187:drug effects* / Q000502:physiology; D009498:Neurotoxins / Q000633:toxicity*; D051381:Rats; D017207:Rats, Sprague-Dawley
D019922:GAP-43 Protein; D008562:Membrane Glycoproteins; D009419:Nerve Tissue Proteins; D009498:Neurotoxins; D002211:Capsaicin