Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1987-1-2
pubmed:abstractText
Data from this laboratory on ketamine-induced analgesia and catalepsy in rats revealed that factors other than dose modified the difference in the latency of the tail flick response (TFLD), a measure of analgesia, and the duration of the loss of the righting reflex (DLRR), a measure of catalepsy. Untreated female rats showed a longer latency than males in their response to a noxious stimulus at midnight, but not at noon. Females also showed a longer loss of righting reflex response to ketamine than did males, whether at noon or midnight; the loss of righting reflex at night was augmented in both. Although females showed analgesia with administration of ketamine at doses smaller than those which induced catatonia, males showed no analgesia without catatonia and comparable loss of the righting reflex occurred at doses much larger than for females. There was a 3-fold increase in the latency of the tail flick response and loss of righting reflex during the winter, as compared with summer, for females treated with ketamine; males showed a similar variation in the loss of righting reflex. Since analgesia is produced by both melatonin and ketamine, and since ketamine appears to share opiate receptors with an endogenous ligand, beta-endorphin, a role was sought for the pineal and melatonin in the variation of responsiveness to ketamine. Pinealectomized rats failed to show augmentation of the loss of righting reflex induced by ketamine at night and mice showed a seasonal variation in the analgesia induced by melatonin.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0028-3908
pubmed:author
pubmed:issnType
Print
pubmed:volume
25
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1095-101
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Seasonal and sex influences on ketamine-induced analgesia and catalepsy in the rat; a possible role for melatonin.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.