Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1989-3-23
pubmed:abstractText
To investigate the mechanism of analgesia noted with electrical stimulation of the thalamic sensory relay nucleus and medial thalamus, modulations of neuronal activities in the periaqueductal gray matter (PAG) were studied in response to electrical stimulations of the ventroposterolateral nucleus (VPL) and parafascicular nucleus (Pf) and to peripheral noxious stimulations in rats. Extracellular single-unit activities were recorded from 102 neurons in the PAG and the adjacent area in animals under halothane anesthesia. A large population (83%) of the PAG neurons reacted to Pf stimulations with a predominantly excitatory response, whereas smaller numbers (43%) responded to VPL stimulations. There was a significant correlation between the response characteristics of Pf and noxious stimulations, whereas no correlation was found between VPL and noxious stimulations. The PAG neurons that were verified antidromically to project to the nucleus raphe magnus showed a similar pattern of response. The excitatory response to the Pf stimulation was partially attenuated by systemic administration of naloxone, whereas that to the VPL stimulation was not affected. These results suggest that part of the analgesic mechanism of medial thalamus stimulation involves activation of the descending pain suppression system by exciting the PAG neurons through the opioid system, while the analgesia produced by sensory relay nucleus stimulation does not involve the PAG neurons or the opioid system.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0022-3085
pubmed:author
pubmed:issnType
Print
pubmed:volume
70
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
446-53
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Dissociated mesencephalic responses to medial and ventral thalamic nuclei stimulation in rats. Relationship to analgesic mechanisms.
pubmed:affiliation
Department of Neurophysiology, Kyushu University Faculty of Medicine, Fukuoka, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't