Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1994-12-19
pubmed:abstractText
Because previous studies suggest an antinociceptive role for the neuromodulator histamine (HA) in the periaqueductal grey or the nearby dorsal raphe (PAG/DR), a detailed pharmacological investigation of the effects of intracerebral HA on the hot-plate nociceptive test was performed in rats. Intracerebral microinjections of HA (1 microgram) into the PAG/DR or into the median raphe evoked a mild, reversible antinociceptive response; injections into lateral or dorsal midbrain evoked either a delayed response or no response, respectively. In the PAG/DR, the HA dose-response curve had an inverted U-shape, showing that HA can induce both antinociceptive (0.3-3 micrograms) and pro-nociceptive (10-30 micrograms) responses. Larger doses of HA (e.g., 100 micrograms) produced irreversible and highly variable antinociceptive responses that were accompanied by behavioral and histopathological changes; such effects, indicative of toxicity, were not observed after 0.3 microgram of HA, the peak antinociceptive dose. HA (0.3 microgram) antinociception was completely inhibited by intracerebral co-administration of the opiate antagonist naloxone (1 ng), the H1-receptor antagonist temelastine (20 pg), and the H2-receptor antagonist tiotidine (1 ng); none of these drugs altered nociceptive scores in the absence of HA. These results show that: (1) HA, a neurotransmitter in the PAG, can evoke antinociception in the absence of other behavioral or toxic effects; and (2) HA antinociception depends on the activation of both opiate and HA receptors in the PAG/DR.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0304-3959
pubmed:author
pubmed:issnType
Print
pubmed:volume
58
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
29-37
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Histamine-induced modulation of nociceptive responses.
pubmed:affiliation
Department of Pharmacology and Toxicology, Albany Medical College (A-136), NY 12208.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.