Source:http://linkedlifedata.com/resource/pubmed/id/11600546
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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
10
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pubmed:dateCreated |
2001-10-15
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pubmed:abstractText |
Antithyroid treatment for Graves' hyperthyroidism restores euthyroidism clinically within 1-2 months, but it is well known that TSH levels can remain suppressed for many months despite normal free T(4) and T(3) levels. This has been attributed to a delayed recovery of the pituitary-thyroid axis. However, we recently showed that the pituitary contains a TSH receptor through which TSH secretion may be down-regulated via a paracrine feedback loop. In Graves' disease, TSH receptor autoantibodies may also bind this pituitary receptor, thus causing continued TSH suppression. This hypothesis was tested in a rat model. Rat thyroids were blocked by methimazole, and the animals were supplemented with L-T(4). They were then injected with purified human IgG from Graves' disease patients at two different titers or with IgG from a healthy control (thyroid hormone binding inhibitory Ig, 591, 127, and < 5 U/liter). Despite similar T(4) and T(3) levels, TSH levels were indeed lower in the animals treated with high TSH receptor autoantibodies containing IgGs; the 48-h mean TSH concentration (mean +/- SEM; n = 8) was 11.6 +/- 1.3 ng/ml compared with 16.2 +/- 0.9 ng/ml in the controls (P < 0.01). The intermediate strength TSH receptor autoantibody-treated animals had levels in between the other two groups (13.5 +/- 2.0 ng/ml). We conclude that TSH receptor autoantibodies can directly suppress TSH levels independently of circulating thyroid hormone levels, suggesting a functioning pituitary TSH receptor.
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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 |
Oct
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pubmed:issn |
0021-972X
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
86
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
4814-7
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pubmed:dateRevised |
2005-11-17
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pubmed:meshHeading |
pubmed-meshheading:11600546-Animals,
pubmed-meshheading:11600546-Autoantibodies,
pubmed-meshheading:11600546-Female,
pubmed-meshheading:11600546-Graves Disease,
pubmed-meshheading:11600546-Immunoglobulin G,
pubmed-meshheading:11600546-Pituitary Gland,
pubmed-meshheading:11600546-Rats,
pubmed-meshheading:11600546-Rats, Wistar,
pubmed-meshheading:11600546-Receptors, Thyrotropin,
pubmed-meshheading:11600546-Thyrotropin
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pubmed:year |
2001
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pubmed:articleTitle |
Suppression of serum TSH by Graves' Ig: evidence for a functional pituitary TSH receptor.
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pubmed:affiliation |
Department of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands. l.j.brokken@amc.uva.nl
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pubmed:publicationType |
Journal Article
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