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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
3
|
| pubmed:dateCreated |
1987-3-4
|
| pubmed:abstractText |
The pyrazolone derivative, metamizol (dipyrone), possesses analgesic, antipyretic, anti-inflammatory and spasmolytic properties. It is often classified as peripherally acting. To test the possibility that a central action of the drug contributes to its antinociceptive and analgesic effects, experiments were carried out in which the tail-flick response to radiant heat, flexor reflex activity in the tibialis anterior muscle and activity in ascending spinal axons evoked by stimulation of afferent C fibres in the sural nerve, and activity of neurones in the periaqueductal grey matter and the substantia nigra were assessed in rats. Metamizol administered by intraperitoneal (i.p.; 10, 20 and 40 mg/kg) or intrathecal (i.t.; 50 to 400 micrograms) injection to intact rats dose-dependently prolonged the tail-flick latency. Administration by i.t. injection to spinal rats was without effect. Intravenous (i.v.) injection of metamizol (140 mg/kg) reduced flexor reflex activity in intact animals, while an i.t. injection to spinal rats was ineffective at a low dose (100 micrograms) or enhanced the reflex activity at a higher dose (400 micrograms). Activity in ascending axons responding to afferent C fibre stimulation was mostly depressed by i.t. injection of metamizol (40, 80 and 140 mg/kg) in rats with an intact spinal cord. Ascending activity was increased by i.t. injection of the drug (100 and 200 micrograms) to spinal rats. Metamizol (140 mg/kg) i.v. increased the activity of neurones in the PAG and reduced that of neurones in the substantia nigra. Metamizol administered by microinjection into the PAG prolonged the tail-flick latency (15-100 micrograms) and depressed C fibre-evoked activity in ascending axons (100 micrograms). The results suggest that a central action is involved in the analgesic effect of metamizol and that this central action manifests itself by an activation of inhibition originating in the PAG.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Dec
|
| pubmed:issn |
0304-3959
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
27
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
373-90
|
| pubmed:dateRevised |
2006-11-15
|
| pubmed:meshHeading |
pubmed-meshheading:3808743-Action Potentials,
pubmed-meshheading:3808743-Aminopyrine,
pubmed-meshheading:3808743-Animals,
pubmed-meshheading:3808743-Dipyrone,
pubmed-meshheading:3808743-Female,
pubmed-meshheading:3808743-Male,
pubmed-meshheading:3808743-Morphine,
pubmed-meshheading:3808743-Naloxone,
pubmed-meshheading:3808743-Nerve Fibers,
pubmed-meshheading:3808743-Neural Inhibition,
pubmed-meshheading:3808743-Pain,
pubmed-meshheading:3808743-Pain Measurement,
pubmed-meshheading:3808743-Periaqueductal Gray,
pubmed-meshheading:3808743-Rats,
pubmed-meshheading:3808743-Rats, Inbred Strains,
pubmed-meshheading:3808743-Reflex,
pubmed-meshheading:3808743-Spinal Cord,
pubmed-meshheading:3808743-Substantia Nigra
|
| pubmed:year |
1986
|
| pubmed:articleTitle |
Activation of inhibition from the periaqueductal grey matter mediates central analgesic effect of metamizol (dipyrone).
|
| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|