Activation of spinal extracellular signaling-regulated kinase-1 and -2 by intraplantar carrageenan in rodents.
We have examined the activation of spinal extracellular signaling-regulated kinase (ERK) in juvenile rats and adult mice after intraplantar carrageenan or saline and its relationship to pain behavior. In rats, intraplantar carrageenan evoked a peak five-fold activation of spinal ERK at 30 min measured by immunoblot. Saline injection resulted in a two-fold activation. This differential ERK activation correlated with a 2.5-fold greater pain response and the development of secondary hyperalgesia in carrageenan-injected rats, whereas both saline and carrageenan produced similar primary hyperalgesia. In mice, carrageenan injection produced a peak 3.5-fold activation of ERK, but saline was ineffective. We conclude that ERK activation may underlie spinal nociceptive processing and secondary hyperalgesia after carrageenan inflammation.
Galan
Alba
A
Department of Physiology, University of Alcalá, Alcalá de Henares, 28871 Madrid, Spain.
Lopez-Garcia
J Antonio
JA
Cervero
Fernando
F
Laird
Jennifer M A
JM
D000344:Afferent Pathways / Q000201:enzymology / Q000503:physiopathology; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects / Q000502:physiology; D002351:Carrageenan / Q000494:pharmacology; D005260:Female; D005528:Foot / Q000294:innervation / Q000503:physiopathology; D006930:Hyperalgesia / Q000139:chemically induced / Q000201:enzymology / Q000503:physiopathology; D007249:Inflammation / Q000139:chemically induced / Q000201:enzymology* / Q000503:physiopathology; D008297:Male; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009475:Neurons, Afferent / Q000201:enzymology*; D009619:Nociceptors / Q000187:drug effects / Q000502:physiology*; D010146:Pain / Q000139:chemically induced / Q000201:enzymology* / Q000503:physiopathology; D017288:Pain Threshold / Q000187:drug effects / Q000502:physiology; D010525:Peripheral Nerves / Q000187:drug effects / Q000503:physiopathology; D051381:Rats; D013116:Spinal Cord / Q000201:enzymology* / Q000503:physiopathology; D009435:Synaptic Transmission / Q000502:physiology; D015854:Up-Regulation / Q000502:physiology*
D002351:Carrageenan; D020928:Mitogen-Activated Protein Kinases