Linked Life Data

10648330

Source:http://linkedlifedata.com/resource/pubmed/id/10648330

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2000-2-28
pubmed:abstractText
Animal studies have suggested that the temporal summation of nociceptive inputs might play a significant role in the development of central sensitization (i.e., hyperexcitability of central nociceptive neurons) and hyperalgesia via the activation of N-methyl-D-aspartate receptors. To further analyze these processes in humans, we evaluated the effects of small systemic doses of ketamine on the temporal summation (i.e., wind-up) of both the nociceptive flexion (R(III)) reflex and sensations of pain in six healthy volunteers. The R(III) reflex was recorded from the biceps femoris and was elicited by electrical stimulation of the sural nerve. First, the recruitment (stimulus/response) curve for the reflex was built using stimuli up to the pain tolerance threshold (applied once every 6 s). A series of 15 stimuli was then applied once a second at an intensity of 1.2 times the reflex threshold. These procedures were performed both before and after the randomized IV injection of either 0.15 mg/kg ketamine or a placebo. The R(III) reflex threshold and its recruitment curve were not significantly altered after the injection of ketamine or placebo. By contrast, the significant increases (i.e., wind-up) in both the reflex responses and the sensations of pain observed during the higher frequency stimulation were significantly reduced after the administration of ketamine, but not placebo. This method might be useful for quantifying and analyzing the wind-up phenomenon and, thus, for studying the neurophysiological and pharmacological mechanisms underlying hyperalgesia in humans. IMPLICATIONS: The wind-up phenomenon (i.e., the progressive increase of the responses induced by repetitive nociceptive stimuli) was characterized in humans by using electrophysiological recordings of the nociceptive flexion reflex. We showed that, as in animals, this phenomenon, which might represent an elementary form of the central sensitization involved in various painful syndromes, depends on the activation of N-methyl-D-aspartate receptors, because it was selectively reduced after the administration of ketamine.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0003-2999
pubmed:author
pubmed:issnType
Print
pubmed:volume
90
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
408-14
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
The effects of ketamine on the temporal summation (wind-up) of the R(III) nociceptive flexion reflex and pain in humans.
pubmed:affiliation
Centre d'Evaluation et de Traitement de la Douleur and Service d'Anesthésie-Réanimation Chirurgicale, Hôpital Ambroise Paré, Boulogne, France.
pubmed:publicationType
Journal Article, Clinical Trial, Randomized Controlled Trial, Research Support, Non-U.S. Gov't