Advanced

Ketamine and xylazine depress sensory-evoked parallel fiber and climbing fiber responses.

Bengtsson, Fredrik LU and Jörntell, Henrik LU (2007) In Journal of Neurophysiology 98(3). p.705-1697
Abstract
Abstract

The last few years have seen an increase in the variety of in vivo experiments used for studying cerebellar physiological mechanisms. A combination of ketamine and xylazine has become a particularly popular form of anesthesia. However, because nonanesthetized control conditions are lacking in these experiments, so far there has been no evaluation of the effects of these drugs on the physiological activity in the cerebellar neuronal network. In the present study, we used the mossy fiber, parallel fiber, and climbing fiber field potentials evoked in the nonanesthetized, decerebrated rat to serve as a control condition against which the effects of intravenous drug injections could be compared. All anesthetics were applied at... (More)
Abstract

The last few years have seen an increase in the variety of in vivo experiments used for studying cerebellar physiological mechanisms. A combination of ketamine and xylazine has become a particularly popular form of anesthesia. However, because nonanesthetized control conditions are lacking in these experiments, so far there has been no evaluation of the effects of these drugs on the physiological activity in the cerebellar neuronal network. In the present study, we used the mossy fiber, parallel fiber, and climbing fiber field potentials evoked in the nonanesthetized, decerebrated rat to serve as a control condition against which the effects of intravenous drug injections could be compared. All anesthetics were applied at doses required for normal maintenance of anesthesia. We found that ketamine substantially depressed the evoked N3 field potential, which is an indicator of the activity in the parallel fiber synapses (-40%), and nearly completely abolished evoked climbing fiber field potentials (-90%). Xylazine severely depressed the N3 field (-75%) and completely abolished the climbing fiber field (-100%). In a combination commonly used for general anesthesia (20:1), ketamine-xylazine injections also severely depressed the N3 field (-75%) and nearly completely abolished the climbing fiber field (-90%). We also observed that lowered body and surface temperatures (<34 degrees C) resulted in a substantial depression of the N3 field (-50%). These results urge for some caution in the interpretations of studies on cerebellar network physiology performed in animals anesthetized with these drugs (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Journal of Neurophysiology
volume
98
issue
3
pages
705 - 1697
publisher
American Physiological Society
external identifiers
  • wos:000249351400054
  • scopus:34548707911
ISSN
0022-3077
DOI
10.1152/jn.00057.2007
language
English
LU publication?
yes
id
1cbf5fa4-d7d9-4a8b-b26b-21b011dec2cb (old id 540979)
alternative location
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=17615140&dopt=Abstract
date added to LUP
2012-12-28 11:07:52
date last changed
2017-01-01 07:14:40
@article{1cbf5fa4-d7d9-4a8b-b26b-21b011dec2cb,
  abstract     = {Abstract<br/><br>
The last few years have seen an increase in the variety of in vivo experiments used for studying cerebellar physiological mechanisms. A combination of ketamine and xylazine has become a particularly popular form of anesthesia. However, because nonanesthetized control conditions are lacking in these experiments, so far there has been no evaluation of the effects of these drugs on the physiological activity in the cerebellar neuronal network. In the present study, we used the mossy fiber, parallel fiber, and climbing fiber field potentials evoked in the nonanesthetized, decerebrated rat to serve as a control condition against which the effects of intravenous drug injections could be compared. All anesthetics were applied at doses required for normal maintenance of anesthesia. We found that ketamine substantially depressed the evoked N3 field potential, which is an indicator of the activity in the parallel fiber synapses (-40%), and nearly completely abolished evoked climbing fiber field potentials (-90%). Xylazine severely depressed the N3 field (-75%) and completely abolished the climbing fiber field (-100%). In a combination commonly used for general anesthesia (20:1), ketamine-xylazine injections also severely depressed the N3 field (-75%) and nearly completely abolished the climbing fiber field (-90%). We also observed that lowered body and surface temperatures (&lt;34 degrees C) resulted in a substantial depression of the N3 field (-50%). These results urge for some caution in the interpretations of studies on cerebellar network physiology performed in animals anesthetized with these drugs},
  author       = {Bengtsson, Fredrik and Jörntell, Henrik},
  issn         = {0022-3077},
  language     = {eng},
  number       = {3},
  pages        = {705--1697},
  publisher    = {American Physiological Society},
  series       = {Journal of Neurophysiology},
  title        = {Ketamine and xylazine depress sensory-evoked parallel fiber and climbing fiber responses.},
  url          = {http://dx.doi.org/10.1152/jn.00057.2007},
  volume       = {98},
  year         = {2007},
}