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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
11
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pubmed:dateCreated |
1998-2-17
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pubmed:abstractText |
The receptors contributing to 5-hydroxytryptamine (5-HT)-induced secretion by rat ileum were investigated in-vitro using selective agonists and antagonists. 5-HT induced a dose-dependent increase in the short-circuit current (SCC) generated by both intact and stripped sheets of rat ileum. 1-Phenylbiguanide, a selective 5-HT3 agonist, and 5-methoxytryptamine, an agonist that lacks affinity for 5-HT3 receptors, also increased the SCC. In intact sheets 5-HT was more effective than either 1-phenylbiguanide or 5-methoxytryptamine, whereas in stripped sheets 5-HT and 5-methoxytryptamine were equipotent, with 1-phenylbiguanide having little effect. Tetrodotoxin abolished the response of intact sheets to 1-phenylbiguanide but only reduced the responses to 5-HT and 5-methoxytryptamine by 57% and 54%, respectively. This inhibition was reduced to 25% in stripped sheets. The 5-HT3 antagonist granisetron abolished the response to 1-phenylbiguanide, but did not alter the effects of 5-HT. Ketanserin, a 5-HT2 antagonist, had a small effect on the actions of 5-methoxytryptamine in intact, but not stripped, sheets and no effect on the response to 5-HT in either preparation. Tropisetron, a 5-HT3 and 5-HT4 antagonist, inhibited the response to 5-methoxytryptamine, but had less effect on the response to 5-HT. Desensitization to 1-phenylbiguanide inhibited the response to 5-HT in intact, but not stripped sheets, whereas desensitization to 5-methoxytryptamine abolished the 5-HT response in stripped sheets, but induced only 42% inhibition in intact sheets. Previous exposure to a combination of both 1-phenylbiguanide and 5-methoxytryptamine abolished the 5-HT-induced increase in SCC in both preparations. The findings suggest that 5-HT-induced ileal secretion involves more than one 5-HT receptor subtype and that both neural and non-neural mechanisms contribute to the response.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Nov
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pubmed:issn |
0022-3573
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
49
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
1114-20
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pubmed:dateRevised |
2010-11-18
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pubmed:meshHeading |
pubmed-meshheading:9401948-Animals,
pubmed-meshheading:9401948-Drug Interactions,
pubmed-meshheading:9401948-Ileum,
pubmed-meshheading:9401948-Male,
pubmed-meshheading:9401948-Rats,
pubmed-meshheading:9401948-Rats, Wistar,
pubmed-meshheading:9401948-Receptors, Serotonin,
pubmed-meshheading:9401948-Serotonin,
pubmed-meshheading:9401948-Serotonin Antagonists,
pubmed-meshheading:9401948-Serotonin Receptor Agonists
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pubmed:year |
1997
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pubmed:articleTitle |
Several receptor subtypes contribute to 5-hydroxytryptamine-induced secretion by rat ileum in-vitro.
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pubmed:affiliation |
Department of Biomedical Science, University of Sheffield, UK.
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pubmed:publicationType |
Journal Article
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