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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
2
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| pubmed:dateCreated |
1987-12-24
|
| pubmed:abstractText |
1 A study has been made of the pharmacology of 5-hydroxytryptamine (5-HT)-induced hyperpolarization responses recorded extracellularly from the rat isolated superior cervical ganglion (SCG). 2 Hyperpolarization responses induced by 5-HT (1 X 10(-8)-1 X 10(-4) M) in the presence of MDL 72222 (1 X 10(-5) M) were not antagonized by phentolamine (1 X 10(-6) M), prazosin (1 X 10(-7)-3 X 10(-7) M), haloperidol (1 X 10(-6) M) or ketanserin (1 X 10(-7)-1 X 10(-6) M). However, the latter two compounds both potentiated and increased the persistence of the hyperpolarization induced by moderate to high concentrations of 5-HT. Spiperone (1 X 10(-7) M) caused similar effects. All further experiments were performed in the presence of ketanserin (1 X 10(-6) M) as well as MDL 72222. 3 8-Hydroxy-2(di-n-propylamino)-tetralin (8-OH-DPAT; 1 X 10(-7)-1 X 10(-4) M) and ipsapirone (3 X 10(-5)-3 X 10(-4) M) behaved as weak hyperpolarizing agonists on the SCG. However, at concentrations below those required to produce hyperpolarization, both compounds acted as unsurmountable antagonists of 5-HT-induced hyperpolarization. 4 5-Carboxamidotryptamine (5-CT; 1 X 10(-9)-1 X 10(-5) M) mimicked the hyperpolarizing activity of 5-HT on the SCG. The EC50 for 5-CT was approximately 9 fold lower than that for 5-HT. 5 Spiperone (1 X 10(-7) - 1 X 10(-5) M) behaved as a reversible competitive antagonist of hyperpolarization responses induced by 5-HT with a pKB value of 7.40 +/- 0.09. Spiperone (1 X 10(-7)-1 X 10(-6) M) also caused concentration-dependent rightward displacement of the 5-CT concentration-hyperpolarization response curve. In this case, the pKB was 7.80 +/- 0.05. 6 (+/-)-Cyanopindolol (3 X 10(-7)-3 X 10(-6) M) caused non-parallel rightward displacements of the 5-HT concentration-response curve. Against 5-CT, (+/-)-cyanopindolol (3 X 10(-7)-3 X 10(-6) M) caused a concentration-independent rightward displacement of the concentration-response curve, accompanied by a large increase in the maximum response. 5-CT-induced hyperpolarization recorded in the presence of (+/-)-cyanopindolol (3 X 10(-7) M) was not significantly antagonized by methiothepin (1 X 10(-6) M) or methysergide (1 X 10(-6) M). 7. It is concluded that 5-HT-induced hyperpolarization of the rat SCG is mediated via a 5-HT1-like receptor which resembles the 5-HT1A binding site. However, a lack of selective drugs precludes more definitive characterization of this receptor.
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| pubmed:commentsCorrections |
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-13651579,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-14838,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-218668,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-23126,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-2859533,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-2871177,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-2875415,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-2932343,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-2935410,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-2936965,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-3676601,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-37098,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-3814917,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-3814920,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-3951568,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-3969066,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-3969067,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-3987810,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-6140042,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-6152223,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-6223827,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-6273186,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-6396525,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-6519175,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-6716262,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-7099138,
http://linkedlifedata.com/resource/pubmed/commentcorrection/3676602-7463047
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| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
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| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Oct
|
| pubmed:issn |
0007-1188
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| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
92
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
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| pubmed:pagination |
417-27
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| pubmed:dateRevised |
2010-5-10
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| pubmed:meshHeading |
pubmed-meshheading:3676602-Animals,
pubmed-meshheading:3676602-Ganglia, Spinal,
pubmed-meshheading:3676602-Male,
pubmed-meshheading:3676602-Membrane Potentials,
pubmed-meshheading:3676602-Rats,
pubmed-meshheading:3676602-Receptors, Serotonin,
pubmed-meshheading:3676602-Serotonin,
pubmed-meshheading:3676602-Serotonin Antagonists
|
| pubmed:year |
1987
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| pubmed:articleTitle |
Pharmacological characterization of 5-hydroxytryptamine-induced hyperpolarization of the rat superior cervical ganglion.
|
| pubmed:affiliation |
Department of Neuropharmacology, Glaxo Group Research Ltd., Ware, Hertfordshire.
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| pubmed:publicationType |
Journal Article,
In Vitro
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