title: NMDA and AMPA receptors contribute to the maintenance of substance P-induced thermal hyperalgesia.
abstract: It is well known that intrathecal administration of substance P (SP) induces thermal hyperalgesia, but the mechanisms underlying the maintenance of SP-induced thermal hyperalgesia remain to be clarified. Thus, to clarify the receptors involved in the maintenance of SP-induced thermal hyperalgesia, the effect of administering SP or glutamate receptor agonists, NMDA or AMPA, under SP-induced thermal hyperalgesia was investigated. Also, the effect of pretreatment with protein kinase inhibitors on scratching behavior by NMDA or AMPA under SP-induced thermal hyperalgesia was examined. Under SP-induced thermal hyperalgesia, the number of scratchings following SP administration was time-dependently suppressed, whereas the number of scratchings after NMDA or AMPA administration was markedly enhanced and SP-induced thermal hyperalgesia was attenuated by pretreatment with NMDA or AMPA receptor antagonist. Furthermore, pretreatment with kinase inhibitors significantly attenuated the enhancement of scratching behavior by NMDA or AMPA under SP-induced thermal hyperalgesia. These findings indicate that SP-induced thermal hyperalgesia may be maintained through the enhanced responsiveness of NMDA or AMPA receptors, but not the receptor of SP, mediated by kinases.
authors.affiliation: Division of Neurobiology, Faculty of Medicine, University of Miyazaki, Kiyotake, Miyazaki 889-1692, Japan.
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Nakayama
authors.forename: Rumi
authors.initials: R
authors.lastname: Naono
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ikeda
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Nishimori
mesh_terms: D000818:Animals; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2 / Q000037:antagonists & inhibitors / Q000502:physiology; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors / Q000502:physiology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors / Q000502:physiology; D006358:Hot Temperature; D006930:Hyperalgesia / Q000378:metabolism* / Q000503:physiopathology; D007278:Injections, Spinal; D008297:Male; D016202:N-Methylaspartate / Q000494:pharmacology; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D018091:Receptors, AMPA / Q000819:agonists / Q000502:physiology*; D016194:Receptors, N-Methyl-D-Aspartate / Q000819:agonists / Q000502:physiology*; D013373:Substance P / Q000494:pharmacology / Q000502:physiology*; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000494:pharmacology
chemical_list: D018091:Receptors, AMPA; D016194:Receptors, N-Methyl-D-Aspartate; D013373:Substance P; D016202:N-Methylaspartate; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D017868:Cyclic AMP-Dependent Protein Kinases; D011493:Protein Kinase C; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D048049:Extracellular Signal-Regulated MAP Kinases