Linked Life Data

2471089

Source:http://linkedlifedata.com/resource/pubmed/id/2471089

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1989-7-10
pubmed:abstractText
Isolated small intestinal segments of the guinea pig were arterially perfused and the release of 5-hydroxytryptamine (5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) into the portal venous effluent measured by HPLC with electrochemical detection. Test substances were applied via the arterial perfusion medium. McN-A-343, pilocarpine and oxotremorine inhibited concentration-dependently the outflow of 5-HT and 5-HIAA. Pirenzepine (0.03-0.1 mumol/l) which can discriminate between M1 and M2-receptor subtypes antagonized completely this inhibitory effect. In the presence of 1 mumol/l tetrodotoxin (TTx), all three muscarine receptor agonists increased the outflow of 5-HT and 5-HIAA. Oxotremorine (1 mumol/l) was most effective and increased the outflow of 5-HT by 145%, that of 5-HIAA by 235%. McN-A-343 and pilocarpine, both at a concentration of 10 mumol/l, increased the outflow of 5-HT by about 40%, that of 5-HIAA by 50% and 71%, respectively. The stimulatory effect of oxotremorine was competitively antagonized by pirenzepine; a pA2 value of 7.70 was calculated. In conclusion, the cholinergic modulation of the release of 5-HT from the enterochromaffin cells consists of an indirect inhibitory (via the release of a neurotransmitter) and a direct stimulatory component. Muscarine receptors mediating the indirect effect may belong to the M1-subtype whereas the direct stimulatory effect may be mediated by a mixed population of M1 and M2 receptors or by a subtype of M1 receptors.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0028-1298
pubmed:author
pubmed:issnType
Print
pubmed:volume
339
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
263-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Characterization of the muscarine receptors involved in the modulation of serotonin release from the vascularly perfused small intestine of guinea pig.
pubmed:affiliation
Department of Pharmacology, University of Mainz, Federal Republic of Germany.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't