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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
4
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pubmed:dateCreated |
1989-7-12
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pubmed:abstractText |
The characteristics of cholecystokinin (CCK) receptors in rat pancreatic acini and in various regions of the brain were examined using synthetic CCK-8 or CCK-7 analogues. 3H-propionylated CCK-8 [( 3H]CCK-8) was used as a ligand. 1) The pancreatic CCK receptor had a single high affinity binding component with a dissociation constant, Kd, of 0.76 nM and a maximum number of specific binding sites, Bmax, of 271.91 fmol/mg protein. On the other hand, the CCK receptor in the cerebral cortex had a Kd of 1.66 nM and a Bmax of 30.15 fmol/mg protein. 2) The order of the potencies of CCK-7 and CCK-8 analogues with a substitution at position 3 or 4 to displace [3H]CCK-8 specific binding to the pancreatic acini was as follows: CCK-8 greater than CCK-7 = SucCCK-7 greater than Suc[Sar3]CCK-7 greater than Suc[D-Trp3]CCK-7 greater than Suc[D-Ala3]CCK-7 greater than [D-Trp4]CCK-8 = [D-Ala4] CCK-8. This order of potencies of CCK analogues was greatly different from that in the cerebral cortex. 3) The carboxy-terminal tetra-peptide (CCK-4) and penta-peptide (CCK-5) had very weak potencies in displacing [3H]CCK-8 binding in the pancreatic acini, which were 20 to 30-fold less than their potencies in the cerebral cortex. These results suggest that the recognition sites for CCK analogues in the pancreatic and brain CCK receptors are different.
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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 |
Apr
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pubmed:issn |
0021-5198
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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 |
471-81
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading |
pubmed-meshheading:2724687-Animals,
pubmed-meshheading:2724687-Binding, Competitive,
pubmed-meshheading:2724687-Brain Chemistry,
pubmed-meshheading:2724687-Male,
pubmed-meshheading:2724687-Membranes,
pubmed-meshheading:2724687-Pancreas,
pubmed-meshheading:2724687-Proteins,
pubmed-meshheading:2724687-Rats,
pubmed-meshheading:2724687-Rats, Inbred Strains,
pubmed-meshheading:2724687-Receptors, Cholecystokinin,
pubmed-meshheading:2724687-Sincalide
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pubmed:year |
1989
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pubmed:articleTitle |
Comparison of CCK-8 receptors in the pancreas and brain of rats using CCK-8 analogues.
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pubmed:affiliation |
Department of Pharmacology, Faculty of Pharmaceutical Sciences, Fukuoka University, Japan.
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pubmed:publicationType |
Journal Article,
Comparative Study
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