Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1998-5-28
pubmed:abstractText
1. A study was made of the effects of 5-carboxamidotryptamine (5-CT) on pressor responses induced in vivo by electrical stimulation of the sympathetic outflow from the spinal cord of pithed rats. All animals had been pretreated with atropine. Sympathetic stimulation (0.1, 0.5, 1 and 5 Hz) resulted in frequency-dependent increases in blood pressure. Intravenous infusion of 5-CT at doses of 0.01, 0.1 and 1 mg kg(-1) min(-1) reduced the pressor effects obtained by electrical stimulation. The inhibitory effect of 5-CT was significantly more pronounced at lower frequencies of stimulation. In the present study we characterized the pharmacological profile of the receptors mediating the above inhibitory effect of 5-CT. 2. The inhibition induced by 0.01 microg kg(-1) min(-1) of 5-CT on sympathetically-induced pressor responses was partially blocked after i.v. treatment with methiothepin (10 microg kg(-1)), WAY-100,635 (100 microg kg(-1)) or GR127935T (250 microg kg(-1)), but was not affected by cyanopindolol (100 microg kg(-1)). 3. The selective 5-HT1A receptor agonist 8-OH-DPAT and the selective 5-HT(1B/1D) receptor agonists sumatriptan and L-694,247 inhibited the pressor response, whereas the 5-HT1B receptor agonists CGS-12066B and CP-93,129 and the 5-HT2C receptor agonist m-CPP did not modify the pressor sympathetic responses. 4. The selective 5-HT1A receptor antagonist WAY-100,635 (100 microg kg(-1)) blocked the inhibition induced by 8-OH-DPAT and the selective 5-HT(1B/1D) receptor antagonist GR127935T (250 microg kg(-1)) abolished the inhibition induced either by L-694,247 or sumatriptan. 5. None of the 5-HT receptor agonists used in our experiments modified the pressor responses induced by exogenous noradrenaline (NA). 6. These results suggest that the presynaptic inhibitory action of 5-CT on the electrically-induced pressor response is mediated by both r-5-HT1D and 5-HT1A receptors.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0007-1188
pubmed:author
pubmed:issnType
Print
pubmed:volume
123
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1205-13
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Characterization of prejunctional 5-HT1 receptors that mediate the inhibition of pressor effects elicited by sympathetic stimulation in the pithed rat.
pubmed:affiliation
Departamento de Fisiología y Farmacología, Facultad de Farmacia, Universidad de Salamanca, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't