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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
2
|
| pubmed:dateCreated |
1995-3-29
|
| pubmed:abstractText |
beta-Adrenoceptors in the guinea pig taenia caecum were investigated by measuring relaxation responses to agonists and by a radioligand binding assay using [3H]CGP 12177. The rightward shift of the isoprenaline concentration-response curve was observed by butoxamine, a beta 2-selective antagonist, and the pA2 value for butoxamine was 6.46. In control preparations, catecholamines caused relaxation with the following rank order of potency: isoprenaline > adrenaline > noradrenaline. However, in the presence of 10(-6) M phentolamine, 3 x 10(-4) M atenolol and 10(-4) M butoxamine, the rank order of potency of the agonists was: isoprenaline > noradrenaline > adrenaline. CGP 12177 caused graded relaxation of the guinea pig taenia caecum, and this response was not influenced by 10(-6) M phentolamine, 3 x 10(-4) M atenolol, 10(-4) M butoxamine or 10(-6) M propranolol. The Scatchard plot of the specific [3H]CGP 12177 binding to microsomal fractions from the guinea pig taenia caecum showed two affinity sites of the receptor: high affinity (KD = 0.64 nM) and low affinity (KD = 142.21 nM) sites. The pKD value of the high affinity site of [3H]CGP 12177 was in agreement with its pA2 value, and that of the low affinity site was in agreement with its pD2 value. These results suggest that isoprenaline-, noradrenaline- and adrenaline-induced relaxations of the guinea pig taenia caecum predominantly involve beta 2- and beta 3-adrenoceptors, whereas CGP 12177-induced relaxation is mediated solely through beta 3-adrenoceptors.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Adrenergic beta-Antagonists,
http://linkedlifedata.com/resource/pubmed/chemical/Atenolol,
http://linkedlifedata.com/resource/pubmed/chemical/Butoxamine,
http://linkedlifedata.com/resource/pubmed/chemical/CGP 12177,
http://linkedlifedata.com/resource/pubmed/chemical/Epinephrine,
http://linkedlifedata.com/resource/pubmed/chemical/Isoproterenol,
http://linkedlifedata.com/resource/pubmed/chemical/Norepinephrine,
http://linkedlifedata.com/resource/pubmed/chemical/Phentolamine,
http://linkedlifedata.com/resource/pubmed/chemical/Propanolamines,
http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Adrenergic, beta
|
| pubmed:status |
MEDLINE
|
| pubmed:month |
Oct
|
| pubmed:issn |
0021-5198
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
66
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
213-20
|
| pubmed:dateRevised |
2006-11-15
|
| pubmed:meshHeading |
pubmed-meshheading:7869606-Adrenergic beta-Antagonists,
pubmed-meshheading:7869606-Animals,
pubmed-meshheading:7869606-Atenolol,
pubmed-meshheading:7869606-Binding, Competitive,
pubmed-meshheading:7869606-Butoxamine,
pubmed-meshheading:7869606-Cecum,
pubmed-meshheading:7869606-Dose-Response Relationship, Drug,
pubmed-meshheading:7869606-Epinephrine,
pubmed-meshheading:7869606-Guinea Pigs,
pubmed-meshheading:7869606-Isoproterenol,
pubmed-meshheading:7869606-Male,
pubmed-meshheading:7869606-Microsomes,
pubmed-meshheading:7869606-Muscle, Smooth,
pubmed-meshheading:7869606-Muscle Relaxation,
pubmed-meshheading:7869606-Norepinephrine,
pubmed-meshheading:7869606-Phentolamine,
pubmed-meshheading:7869606-Propanolamines,
pubmed-meshheading:7869606-Radioligand Assay,
pubmed-meshheading:7869606-Receptors, Adrenergic, beta
|
| pubmed:year |
1994
|
| pubmed:articleTitle |
Involvement of beta 3-adrenoceptor in the relaxation response in guinea pig taenia caecum.
|
| pubmed:affiliation |
Department of Chemical Pharmacology, Toho University School of Pharmaceutical Sciences, Chiba, Japan.
|
| pubmed:publicationType |
Journal Article,
In Vitro,
Research Support, Non-U.S. Gov't
|