Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
1990-4-26
pubmed:abstractText
Isolated segments of the guinea-pig small intestine and the guinea-pig stomach were vascularly perfused and the release of 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid into the portal venous effluent determined by high pressure liquid chromatography with electrochemical detection. Test substances were applied intraarterially. The benzodiazepine receptor agonist, midazolam, concentration-dependently increased (by 58%, at 1 nmol/l) and decreased (by 32%, at 100 nmol/l) the release of 5-HT from small intestine preparations. Both effects were blocked by the benzodiazepine receptor antagonist flumazenil (10 nmol/l) The stimulatory effect of midazolam was also abolished in the presence of tetrodotoxin (1 mumol/l) or scopolamine (100 nmol/l). In the absence of tetrodotoxin, flumazenil (10 nmol/l) alone decreased the release of 5-HT from the small intestine by 41%, but it increased the release of 5-HT by 50% in the presence of tetrodotoxin. Both effects of flumazenil were abolished in the presence of bicuculline (50 mumol/l). In the absence of tetrodotoxin, flumazenil (10 nmol/l) decreased also the release of 5-HT and its metabolite from the perfused stomach by about 40%, whereas midazolam (1 nmol/l) caused an increase by about 60%. In conclusion, benzodiazepine receptors modulate the previously described intrinsic GABAergic regulation of 5-HT release from enterochromaffin cells in the guinea-pig intestine. It is suggested that an endogenous benzodiazepine-like substance of non-neuronal origin is present in the small intestine and stomach of the guinea-pig.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0028-1298
pubmed:author
pubmed:issnType
Print
pubmed:volume
341
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:articleTitle
Effects of the benzodiazepine receptor agonist midazolam and antagonist flumazenil on 5-hydroxytryptamine release from guinea-pig intestine in vitro. Indirect support for a "natural" benzodiazepine-like substance in the intestine.
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