Nociceptive transmission to rat primary somatosensory cortex - comparison of sedative and analgesic effects.
Granmo, Marcus LU ; Jensen, Tanja LU and Schouenborg, Jens LU
(2013)
In PLoS ONE
8(1).
- Abstract
- CO(2)-laser C-fibre evoked cortical potentials (LCEPs) is a potentially useful animal model for studies of pain mechanisms. A potential confounding factor when assessing analgesic effects of systemically administered drugs using LCEP is sedation. This study aims to clarify: 1) the relation between level of anaesthesia and magnitude of LCEP, 2) the effects of a sedative and an analgesic on LCEP and dominant EEG frequency 3) the effects of a sedative and analgesic on LCEP when dominant EEG frequency is kept stable. LCEP and EEG were recorded in isoflurane/nitrous-oxide anaesthetized rats. Increasing isoflurane level gradually reduced LCEPs and lowered dominant EEG frequencies. Systemic midazolam (10 μmol/kg) profoundly reduced LCEP (19% of... (More)
- CO(2)-laser C-fibre evoked cortical potentials (LCEPs) is a potentially useful animal model for studies of pain mechanisms. A potential confounding factor when assessing analgesic effects of systemically administered drugs using LCEP is sedation. This study aims to clarify: 1) the relation between level of anaesthesia and magnitude of LCEP, 2) the effects of a sedative and an analgesic on LCEP and dominant EEG frequency 3) the effects of a sedative and analgesic on LCEP when dominant EEG frequency is kept stable. LCEP and EEG were recorded in isoflurane/nitrous-oxide anaesthetized rats. Increasing isoflurane level gradually reduced LCEPs and lowered dominant EEG frequencies. Systemic midazolam (10 μmol/kg) profoundly reduced LCEP (19% of control) and lowered dominant EEG frequency. Similarly, morphine 1 and 3 mg/kg reduced LCEP (39%, 12% of control, respectively) and decreased EEG frequency. When keeping the dominant EEG frequency stable, midazolam caused no significant change of LCEP. Under these premises, morphine at 3 mg/kg, but not 1 mg/kg, caused a significant LCEP reduction (26% of control). In conclusion, the present data indicate that the sedative effects should be accounted for when assessing the analgesic effects of drug. Furthermore, it is suggested that LCEP, given that changes in EEG induced by sedation are compensated for, can provide information about the analgesic properties of systemically administrated drugs. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/3438696
- author
- Granmo, Marcus
LU
; Jensen, Tanja
LU
and Schouenborg, Jens
LU
- organization
- publishing date
- 2013
- type
- Contribution to journal
- publication status
- published
- subject
- in
- PLoS ONE
- volume
- 8
- issue
- 1
- article number
- e53966
- publisher
- Public Library of Science (PLoS)
- external identifiers
-
- wos:000313429800074
- pmid:23320109
- scopus:84872173131
- pmid:23320109
- ISSN
- 1932-6203
- DOI
- 10.1371/journal.pone.0053966
- language
- English
- LU publication?
- yes
- id
- 2265c551-976d-4362-926c-8abb7d2d5dd5 (old id 3438696)
- alternative location
- http://www.ncbi.nlm.nih.gov/pubmed/23320109?dopt=Abstract
- date added to LUP
- 2016-04-01 13:02:07
- date last changed
- 2024-05-22 05:32:20
@article{2265c551-976d-4362-926c-8abb7d2d5dd5,
abstract = {{CO(2)-laser C-fibre evoked cortical potentials (LCEPs) is a potentially useful animal model for studies of pain mechanisms. A potential confounding factor when assessing analgesic effects of systemically administered drugs using LCEP is sedation. This study aims to clarify: 1) the relation between level of anaesthesia and magnitude of LCEP, 2) the effects of a sedative and an analgesic on LCEP and dominant EEG frequency 3) the effects of a sedative and analgesic on LCEP when dominant EEG frequency is kept stable. LCEP and EEG were recorded in isoflurane/nitrous-oxide anaesthetized rats. Increasing isoflurane level gradually reduced LCEPs and lowered dominant EEG frequencies. Systemic midazolam (10 μmol/kg) profoundly reduced LCEP (19% of control) and lowered dominant EEG frequency. Similarly, morphine 1 and 3 mg/kg reduced LCEP (39%, 12% of control, respectively) and decreased EEG frequency. When keeping the dominant EEG frequency stable, midazolam caused no significant change of LCEP. Under these premises, morphine at 3 mg/kg, but not 1 mg/kg, caused a significant LCEP reduction (26% of control). In conclusion, the present data indicate that the sedative effects should be accounted for when assessing the analgesic effects of drug. Furthermore, it is suggested that LCEP, given that changes in EEG induced by sedation are compensated for, can provide information about the analgesic properties of systemically administrated drugs.}},
author = {{Granmo, Marcus and Jensen, Tanja and Schouenborg, Jens}},
issn = {{1932-6203}},
language = {{eng}},
number = {{1}},
publisher = {{Public Library of Science (PLoS)}},
series = {{PLoS ONE}},
title = {{Nociceptive transmission to rat primary somatosensory cortex - comparison of sedative and analgesic effects.}},
url = {{https://lup.lub.lu.se/search/files/3121429/3738808.pdf}},
doi = {{10.1371/journal.pone.0053966}},
volume = {{8}},
year = {{2013}},
}