help button home button Endocrine Society JCEM
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
This Article
Right arrow Submit a related Letter to the Editor
Right arrow Alert me when this article is cited
Right arrow Alert me when eLetters are posted
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Request Copyright Permission
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Chanson, P.
Right arrow Articles by Peillon, F.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Chanson, P.
Right arrow Articles by Peillon, F.

Journal of Clinical Endocrinology & Metabolism, Vol 66, 447-450, Copyright © 1988 by Endocrine Society

ARTICLES

Absence of receptors for thyrotropin (TSH)-releasing hormone in human TSH-secreting pituitary adenomas associated with hyperthyroidism

P Chanson, JY Li, M Le Dafniet, P Derome, M Kujas, A Murat, G Charpentier, J Racadot and F Peillon
Service d'Endocrinologie, Hopital Lariboisiere, Paris, France.

In patients with TSH-secreting pituitary adenomas associated with hyperthyroidism, TSH secretion usually does not respond to exogenous TRH stimulation. To determine the basis for this unresponsiveness, we studied TRH binding to the membranes of two such TSH-secreting pituitary adenomas. The patients, a 28-yr-old man and a 60-yr-old woman, had clinical and biochemical hyperthyroidism with increased serum TSH levels (15.7 and 14 mU/L, respectively; normal range, 1.1- 7.2) and alpha-subunit to TSH molar ratios greater than 1 (2.4 and 1.7, respectively). Neither patients had an increase in serum TSH in response to TRH (200 micrograms, iv). Immunocytochemistry of the two adenomas, removed by transsphenoidal surgery showed a pure population of thyrotropic cells. Binding studies were performed by incubation of tumor cell membrane suspensions with increasing amounts of [3H]TRH. Two PRL-secreting adenomas and one normal human pituitary were used as controls. The characteristics of the TRH-binding sites from the control tissues were similar to those previously reported (Kd, 56, 30, and 49 nM; maximum binding, 187, 46, and 94 fmol/mg protein, respectively). In contrast, no specific TRH binding was found in the two TSH-secreting adenomas. We conclude that the unresponsiveness of TSH after TRH administration is related to the absence of specific TRH-binding sites in these thyrotropic tumors.


This article has been cited by other articles:


Home page
 J. Clin. Endocrinol. Metab.Home page
F. Brucker-Davis, E. H. Oldfield, M. C. Skarulis, J. L. Doppman, and B. D. Weintraub
Thyrotropin-Secreting Pituitary Tumors: Diagnostic Criteria, Thyroid Hormone Sensitivity, and Treatment Outcome in 25 Patients Followed at the National Institutes of Health
J. Clin. Endocrinol. Metab., February 1, 1999; 84(2): 476 - 486.
[Abstract] [Full Text]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Endocrinology Endocrine Reviews J. Clin. End. & Metab.
Molecular Endocrinology Recent Prog. Horm. Res. All Endocrine Journals
Copyright © 1988 by The Endocrine Society