Bone cancer induces a unique central sensitization through synaptic changes in a wide area of the spinal cord

<p>Abstract</p> <p>Background</p> <p>Chronic bone cancer pain is thought to be partly due to central sensitization. Although murine models of bone cancer pain revealed significant neurochemical changes in the spinal cord, it is not known whether this produces functional...

Full description

Bibliographic Details
Main Authors: Uta Daisuke, Kawamata Tomoyuki, Furue Hidemasa, Yanagisawa Yoshikazu, Yamamoto Jun, Furuse Shingo, Katafuchi Toshihiko, Imoto Keiji, Iwamoto Yukihide, Yoshimura Megumu
Format: Article
Language:English
Published: SAGE Publishing 2010-07-01
Series:Molecular Pain
Online Access:http://www.molecularpain.com/content/6/1/38
_version_ 1819182463015976960
author Uta Daisuke
Kawamata Tomoyuki
Furue Hidemasa
Yanagisawa Yoshikazu
Yamamoto Jun
Furuse Shingo
Katafuchi Toshihiko
Imoto Keiji
Iwamoto Yukihide
Yoshimura Megumu
author_facet Uta Daisuke
Kawamata Tomoyuki
Furue Hidemasa
Yanagisawa Yoshikazu
Yamamoto Jun
Furuse Shingo
Katafuchi Toshihiko
Imoto Keiji
Iwamoto Yukihide
Yoshimura Megumu
author_sort Uta Daisuke
collection DOAJ
description <p>Abstract</p> <p>Background</p> <p>Chronic bone cancer pain is thought to be partly due to central sensitization. Although murine models of bone cancer pain revealed significant neurochemical changes in the spinal cord, it is not known whether this produces functional alterations in spinal sensory synaptic transmission. In this study, we examined excitatory synaptic responses evoked in substantia gelatinosa (SG, lamina II) neurons in spinal cord slices of adult mice bearing bone cancer, using whole-cell voltage-clamp recording techniques.</p> <p>Results</p> <p>Mice at 14 to 21 days after sarcoma implantation into the femur exhibited hyperalgesia to mechanical stimuli applied to the skin of the ipsilateral hind paw, as well as showing spontaneous and movement evoked pain-related behaviors. SG neurons exhibited spontaneous excitatory postsynaptic currents (EPSCs). The amplitudes of spontaneous EPSCs were significantly larger in cancer-bearing than control mice without any changes in passive membrane properties of SG neurons. In the presence of TTX, the amplitude of miniature EPSCs in SG neurons was increased in cancer-bearing mice and this was observed for cells sampled across a wide range of lumbar segmental levels. Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor- and <it>N</it>-methyl-<it>D</it>-aspartate (NMDA) receptor-mediated EPSCs evoked by focal stimulation were also enhanced in cancer-bearing mice. Dorsal root stimulation elicited mono- and/or polysynaptic EPSCs that were caused by the activation of Aδ and/or C afferent fibers in SG neurons from both groups of animals. The number of cells receiving monosynaptic inputs from Aδ and C fibers was not different between the two groups. However, the amplitude of the monosynaptic C fiber-evoked EPSCs and the number of SG neurons receiving polysynaptic inputs from Aδ and C fibers were increased in cancer-bearing mice.</p> <p>Conclusions</p> <p>These results show that spinal synaptic transmission mediated through Aδ and C fibers is enhanced in the SG across a wide area of lumbar levels following sarcoma implantation in the femur. This widespread spinal sensitization may be one of the underlying mechanisms for the development of chronic bone cancer pain.</p>
first_indexed 2024-12-22T22:46:31Z
format Article
id doaj.art-33fbe59d14f444a1b1cfe7599ae25c51
institution Directory Open Access Journal
issn 1744-8069
language English
last_indexed 2024-12-22T22:46:31Z
publishDate 2010-07-01
publisher SAGE Publishing
record_format Article
series Molecular Pain
spelling doaj.art-33fbe59d14f444a1b1cfe7599ae25c512022-12-21T18:10:04ZengSAGE PublishingMolecular Pain1744-80692010-07-01613810.1186/1744-8069-6-38Bone cancer induces a unique central sensitization through synaptic changes in a wide area of the spinal cordUta DaisukeKawamata TomoyukiFurue HidemasaYanagisawa YoshikazuYamamoto JunFuruse ShingoKatafuchi ToshihikoImoto KeijiIwamoto YukihideYoshimura Megumu<p>Abstract</p> <p>Background</p> <p>Chronic bone cancer pain is thought to be partly due to central sensitization. Although murine models of bone cancer pain revealed significant neurochemical changes in the spinal cord, it is not known whether this produces functional alterations in spinal sensory synaptic transmission. In this study, we examined excitatory synaptic responses evoked in substantia gelatinosa (SG, lamina II) neurons in spinal cord slices of adult mice bearing bone cancer, using whole-cell voltage-clamp recording techniques.</p> <p>Results</p> <p>Mice at 14 to 21 days after sarcoma implantation into the femur exhibited hyperalgesia to mechanical stimuli applied to the skin of the ipsilateral hind paw, as well as showing spontaneous and movement evoked pain-related behaviors. SG neurons exhibited spontaneous excitatory postsynaptic currents (EPSCs). The amplitudes of spontaneous EPSCs were significantly larger in cancer-bearing than control mice without any changes in passive membrane properties of SG neurons. In the presence of TTX, the amplitude of miniature EPSCs in SG neurons was increased in cancer-bearing mice and this was observed for cells sampled across a wide range of lumbar segmental levels. Alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor- and <it>N</it>-methyl-<it>D</it>-aspartate (NMDA) receptor-mediated EPSCs evoked by focal stimulation were also enhanced in cancer-bearing mice. Dorsal root stimulation elicited mono- and/or polysynaptic EPSCs that were caused by the activation of Aδ and/or C afferent fibers in SG neurons from both groups of animals. The number of cells receiving monosynaptic inputs from Aδ and C fibers was not different between the two groups. However, the amplitude of the monosynaptic C fiber-evoked EPSCs and the number of SG neurons receiving polysynaptic inputs from Aδ and C fibers were increased in cancer-bearing mice.</p> <p>Conclusions</p> <p>These results show that spinal synaptic transmission mediated through Aδ and C fibers is enhanced in the SG across a wide area of lumbar levels following sarcoma implantation in the femur. This widespread spinal sensitization may be one of the underlying mechanisms for the development of chronic bone cancer pain.</p>http://www.molecularpain.com/content/6/1/38
spellingShingle Uta Daisuke
Kawamata Tomoyuki
Furue Hidemasa
Yanagisawa Yoshikazu
Yamamoto Jun
Furuse Shingo
Katafuchi Toshihiko
Imoto Keiji
Iwamoto Yukihide
Yoshimura Megumu
Bone cancer induces a unique central sensitization through synaptic changes in a wide area of the spinal cord
Molecular Pain
title Bone cancer induces a unique central sensitization through synaptic changes in a wide area of the spinal cord
title_full Bone cancer induces a unique central sensitization through synaptic changes in a wide area of the spinal cord
title_fullStr Bone cancer induces a unique central sensitization through synaptic changes in a wide area of the spinal cord
title_full_unstemmed Bone cancer induces a unique central sensitization through synaptic changes in a wide area of the spinal cord
title_short Bone cancer induces a unique central sensitization through synaptic changes in a wide area of the spinal cord
title_sort bone cancer induces a unique central sensitization through synaptic changes in a wide area of the spinal cord
url http://www.molecularpain.com/content/6/1/38
work_keys_str_mv AT utadaisuke bonecancerinducesauniquecentralsensitizationthroughsynapticchangesinawideareaofthespinalcord
AT kawamatatomoyuki bonecancerinducesauniquecentralsensitizationthroughsynapticchangesinawideareaofthespinalcord
AT furuehidemasa bonecancerinducesauniquecentralsensitizationthroughsynapticchangesinawideareaofthespinalcord
AT yanagisawayoshikazu bonecancerinducesauniquecentralsensitizationthroughsynapticchangesinawideareaofthespinalcord
AT yamamotojun bonecancerinducesauniquecentralsensitizationthroughsynapticchangesinawideareaofthespinalcord
AT furuseshingo bonecancerinducesauniquecentralsensitizationthroughsynapticchangesinawideareaofthespinalcord
AT katafuchitoshihiko bonecancerinducesauniquecentralsensitizationthroughsynapticchangesinawideareaofthespinalcord
AT imotokeiji bonecancerinducesauniquecentralsensitizationthroughsynapticchangesinawideareaofthespinalcord
AT iwamotoyukihide bonecancerinducesauniquecentralsensitizationthroughsynapticchangesinawideareaofthespinalcord
AT yoshimuramegumu bonecancerinducesauniquecentralsensitizationthroughsynapticchangesinawideareaofthespinalcord