Spinal NMDA-receptor dependent amplification of nociceptive transmission to rat primary somatosensory cortex (SI).
(2003) In Pain 104(1-2). p.195-200- Abstract
- The role of NMDA mechanisms in spinal pathways mediating acute nociceptive input to the somatosensory cortex is not clear. In this study, the effect of NMDA-antagonists on nociceptive C fibre transmission to the primary somatosensory cortex (SI) was investigated. Cortical field potentials evoked by CO2-laser stimulation of the skin were recorded in the halothane/nitrous oxide anaesthetized rat.
The SI nociceptive evoked potential (EP) amplitudes were dependent on the frequency of noxious heat stimulation. The amplitudes of SI potentials evoked by CO2-laser pulses (duration 15–20 ms, stimulation energy 21–28 mJ/mm2) delivered at a frequency of 0.1 Hz were approximately 40% of the amplitudes of potentials evoked by 1.0 Hz... (More) - The role of NMDA mechanisms in spinal pathways mediating acute nociceptive input to the somatosensory cortex is not clear. In this study, the effect of NMDA-antagonists on nociceptive C fibre transmission to the primary somatosensory cortex (SI) was investigated. Cortical field potentials evoked by CO2-laser stimulation of the skin were recorded in the halothane/nitrous oxide anaesthetized rat.
The SI nociceptive evoked potential (EP) amplitudes were dependent on the frequency of noxious heat stimulation. The amplitudes of SI potentials evoked by CO2-laser pulses (duration 15–20 ms, stimulation energy 21–28 mJ/mm2) delivered at a frequency of 0.1 Hz were approximately 40% of the amplitudes of potentials evoked by 1.0 Hz stimulation.
After intrathecal lumbar application of either of the NMDA-antagonists CPP or MK-801, the amplitudes of nociceptive SI potentials, evoked by 1.0 Hz stimulation of the contralateral hindpaw, were reduced to approximately 40% of controls. By contrast, field potentials evoked by 0.1 Hz stimulation of the hindpaw were unaffected by MK-801.
SI potentials evoked by 1.0 Hz stimulation of the contralateral forepaw did not change after lumbar application of CPP or MK-801, indicating that the depression of hindpaw EPs was due to a segmental effect in the spinal cord.
It is concluded that spinal NMDA-receptor mechanisms amplify the acute transmission of nociceptive C fiber input to SI in a frequency-dependent way. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/116665
- author
- Kalliomäki, Jarkko ; Granmo, Marcus LU and Schouenborg, Jens LU
- organization
- publishing date
- 2003
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- C fibre, Nociception, Pain, Somatosensory cortex, NMDA-receptor, Wind-up
- in
- Pain
- volume
- 104
- issue
- 1-2
- pages
- 195 - 200
- publisher
- Elsevier
- external identifiers
-
- wos:000184262700021
- pmid:12855329
- scopus:0037823487
- ISSN
- 1872-6623
- DOI
- 10.1016/S0304-3959(03)00002-2
- language
- English
- LU publication?
- yes
- id
- 20f4d8e8-b8f6-4f1f-af9b-968f4a449493 (old id 116665)
- alternative location
- http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12855329&dopt=Abstract
- date added to LUP
- 2016-04-01 12:14:55
- date last changed
- 2024-04-09 06:06:27
@article{20f4d8e8-b8f6-4f1f-af9b-968f4a449493, abstract = {{The role of NMDA mechanisms in spinal pathways mediating acute nociceptive input to the somatosensory cortex is not clear. In this study, the effect of NMDA-antagonists on nociceptive C fibre transmission to the primary somatosensory cortex (SI) was investigated. Cortical field potentials evoked by CO2-laser stimulation of the skin were recorded in the halothane/nitrous oxide anaesthetized rat.<br/><br> <br/><br> The SI nociceptive evoked potential (EP) amplitudes were dependent on the frequency of noxious heat stimulation. The amplitudes of SI potentials evoked by CO2-laser pulses (duration 15–20 ms, stimulation energy 21–28 mJ/mm2) delivered at a frequency of 0.1 Hz were approximately 40% of the amplitudes of potentials evoked by 1.0 Hz stimulation.<br/><br> <br/><br> After intrathecal lumbar application of either of the NMDA-antagonists CPP or MK-801, the amplitudes of nociceptive SI potentials, evoked by 1.0 Hz stimulation of the contralateral hindpaw, were reduced to approximately 40% of controls. By contrast, field potentials evoked by 0.1 Hz stimulation of the hindpaw were unaffected by MK-801.<br/><br> <br/><br> SI potentials evoked by 1.0 Hz stimulation of the contralateral forepaw did not change after lumbar application of CPP or MK-801, indicating that the depression of hindpaw EPs was due to a segmental effect in the spinal cord.<br/><br> <br/><br> It is concluded that spinal NMDA-receptor mechanisms amplify the acute transmission of nociceptive C fiber input to SI in a frequency-dependent way.}}, author = {{Kalliomäki, Jarkko and Granmo, Marcus and Schouenborg, Jens}}, issn = {{1872-6623}}, keywords = {{C fibre; Nociception; Pain; Somatosensory cortex; NMDA-receptor; Wind-up}}, language = {{eng}}, number = {{1-2}}, pages = {{195--200}}, publisher = {{Elsevier}}, series = {{Pain}}, title = {{Spinal NMDA-receptor dependent amplification of nociceptive transmission to rat primary somatosensory cortex (SI).}}, url = {{http://dx.doi.org/10.1016/S0304-3959(03)00002-2}}, doi = {{10.1016/S0304-3959(03)00002-2}}, volume = {{104}}, year = {{2003}}, }