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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
4
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pubmed:dateCreated |
1977-4-30
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pubmed:abstractText |
Propranolol, a beta adrenergic blocking drug, is known to inhibit the thyrotropin (TSH) stimulation of adenosine-3',5'-monophosphate (cyclic AMP production in thyroid membranes but the mechansim of this inhibitory action is known. We have therefore investigated the influence of propranolol on the binding of 125I-labelled TSH to human thyroid membranes. Both d- and l-propranolol were found to enhance the binding of 125I-labelled TSH to thyroid membranes. The amount of label bound increased from about 30% in the absence of propranolol to about 60% in the presence of 3.3 x 10(-3)M propranolol. Scatchard analysis of the binding data indicated that propranolol increased the association constant of the thyrotropin-thyrotropin receptor interaction. Practolol, lithium carbonate, methimazole, and somatostatin had no effect on thyrotropin binding. This effect of propranolol appeared to be due to a direct reversible action of propranolol on the thyroid membranes and could be attributed to the membrane-disrupting properties of the drug rather than its beta-blocking activity. The increased TSH receptor occupancy which resulted from the increased association constant of the TSH-thyroid membrane interaction corresponded with a decrease in TSH-stimulated cyclic AMP formation. These data could indicate that propranolol reduced the efficiency of the receptor-adenylyl cyclase coupling system.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
AIM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Apr
|
pubmed:issn |
0013-7227
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
100
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
974-9
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pubmed:dateRevised |
2009-10-27
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pubmed:meshHeading |
pubmed-meshheading:189996-Cell Membrane,
pubmed-meshheading:189996-Cyclic AMP,
pubmed-meshheading:189996-Humans,
pubmed-meshheading:189996-Propranolol,
pubmed-meshheading:189996-Receptors, Cell Surface,
pubmed-meshheading:189996-Stereoisomerism,
pubmed-meshheading:189996-Thyroid Gland,
pubmed-meshheading:189996-Thyrotropin
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pubmed:year |
1977
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pubmed:articleTitle |
The influence of propranolol on the thyrotropin receptor.
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pubmed:publicationType |
Journal Article,
In Vitro
|