Nerve growth factor modulates the activation status and fast axonal transport of ERK 1/2 in adult nociceptive neurones.
Mature dorsal root ganglion cells respond to neurotrophins, and the intracellular signalling pathways activated by neurotrophins have been characterized in vitro. We have now used immunocytochemistry and Western blots to examine the expression and activation of extracellular signal-regulated protein kinase-1/2 (ERK) in rat dorsal root ganglion cells in vivo, using antisera to total (tERK) and phosphorylated (pERK) forms. This has revealed a number of novel findings. tERK immunoreactivity is present in most dorsal root ganglion cells but is expressed most strongly in small (nociceptive) cells and, surprisingly, is absent in a population of large cells that expressed trkB or trkC but mainly lack p75(NTR) immunoreactivity. In contrast pERK is prominent in a few trkA cells and in satellite glial cells, and is further increased by NGF treatment. tERK and pERK both undergo fast anterograde and retrograde axonal transport, indicated by accumulation at a sciatic nerve ligature, and NGF reduces the level of retrograde pERK transport.
Averill
S
S
Department of Neuroscience, St. Bartholomew's School of Medicine and Dentistry, Queen Mary University of London, London, UK.
Delcroix
J D
JD
Michael
G J
GJ
Tomlinson
D R
DR
Fernyhough
P
P
Priestley
J V
JV
D000375:Aging / Q000502:physiology; D000818:Animals; D001370:Axonal Transport / Q000187:drug effects* / Q000502:physiology; D001369:Axons / Q000187:drug effects / Q000201:enzymology / Q000648:ultrastructure; D048429:Cell Size / Q000502:physiology; D005727:Ganglia, Spinal / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D007150:Immunohistochemistry; D008026:Ligation; D008297:Male; D020928:Mitogen-Activated Protein Kinases / Q000187:drug effects* / Q000378:metabolism; D020932:Nerve Growth Factor / Q000378:metabolism / Q000494:pharmacology*; D009475:Neurons, Afferent / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D009619:Nociceptors / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D010766:Phosphorylation; D051381:Rats; D017208:Rats, Wistar; D020800:Receptor, Nerve Growth Factor; D020917:Receptor, trkA / Q000378:metabolism; D020813:Receptor, trkB / Q000378:metabolism; D020812:Receptor, trkC / Q000378:metabolism; D017475:Receptors, Nerve Growth Factor / Q000378:metabolism; D012584:Sciatic Nerve / Q000187:drug effects / Q000201:enzymology / Q000601:surgery
D020800:Receptor, Nerve Growth Factor; D017475:Receptors, Nerve Growth Factor; D020932:Nerve Growth Factor; D020917:Receptor, trkA; D020813:Receptor, trkB; D020812:Receptor, trkC; D020928:Mitogen-Activated Protein Kinases