JOSIAH BROWN, M.D.; INDER J. CHOPRA, M.D.; JAMES S. CORNELL, Ph.D.; JEROME M. HERSHMAN, M.D.; DAVID H. SOLOMON, M.D.; ROBERT P. ULLER, M.D.; ANDRE J. VAN HERLE, M.D.
The pituitary thyrotrophin reserve in 55 patients was tested with thyrotrophin-releasing hormone, and only 28% with deficient responses were hypothyroid; in three patients with hypothalamic disorders the response was delayed but otherwise normal. Three pituitary hormones, thyrotrophin, luteinizing hormone, and follicle-stimulating hormone, contain the same alpha polypeptide chain but different beta chains that confer specificity. Although the serum triiodothyronine (T3) concentration is 1/75th that of thyroxine (T4), its greater volume of distribution (threefold) and disappearance rate (sixfold) results in a T3 turnover one third to one fourth that of T4. Approximately 20% to 33% of T3 comes from the thyroid gland, the remainder from T4. But T4, a prohormone for T3, also contributes hormonal effects. The features of Graves' disease suggest it is an autoimmune disorder, but long-acting thyroid stimulator does not correlate with level or control of thyroid function. The serum thyroglobulin level is higher in women (6.0 ng/ml) than men (3.4 ng/ml); the levels are stable, higher in the newborn than in their mothers; and they rise after thyroid stimulation and fall after suppression. Thyroglobulin levels are elevated during active subacute thyroiditis and are persistently high in hyperthyroidism.
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BROWN J, CHOPRA IJ, CORNELL JS, HERSHMAN JM, SOLOMON DH, ULLER RP, et al. Thyroid Physiology in Health and Disease. Ann Intern Med. 1974;81:68–81. doi: 10.7326/0003-4819-81-1-68
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Published: Ann Intern Med. 1974;81(1):68-81.
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Print ISSN: 0003-4819 | Online ISSN: 1539-3704
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