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Related to Free Triiodothyronine: free thyroxine, FT3, Ft³, Free T4


 (trī′ī-ō′dō-thī′rə-nēn′, -ī-ŏd′ō-)
n. Abbr. T3
An iodine-containing hormone, C15H12I3NO4, produced by the thyroid gland and similar to but more potent than thyroxine. A synthetic form (liothyronine) is used in the treatment of hypothyroidism.

[tri- + iodo- + thyronine, an amino acid (thyr(o)- + -on(e) + -ine).]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Biochemistry) an amino acid hormone that contains iodine and is secreted by the thyroid gland with thyroxine, to which it has a similar action. Formula: C15H12I3NO4
[C20: from tri- + iodo- + thyro- + -ine2]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌtraɪ aɪˌoʊ doʊˈθaɪ rəˌnin, -aɪˌɒd oʊ-)

a thyroid hormone, C15H12I3NO4, similar to thyroxine but more potent: preparations of it used in treating hypothyroidism.
[1950–55; tri- + iod(ine) + -o- + thyronine (perhaps derivative, with -one, of thyroxine)]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.triiodothyronine - thyroid hormone similar to thyroxine but with one less iodine atom per molecule and produced in smaller quantity; exerts the same biological effects as thyroxine but is more potent and briefer
thyroid hormone - any of several closely related compounds that are produced by the thyroid gland and are active metabolically
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
Abbreviations CHD: Coronary heart disease CVD: Cardiovascular disease FT3: Free triiodothyronine FT4: Free thyroxine HbA1c: Glycated hemoglobin HDL: High-density lipoprotein cholesterol LDL-C: Low-density lipoprotein cholesterol TC: Total cholesterol TG: Triglycerides T2DM: Type 2 diabetes mellitus UKPDS: United Kingdom Prospective Diabetes Study.
Fang et al., "Free triiodothyronine level correlates with myocardial injury and prognosis in idiopathic
CRP: C-reactive protein; free T3: free triiodothyronine; free T4: free thyroxine; KI: potassium iodide; MPOANCA: myeloperoxidase-anti-neutrophil cytoplasmic antibody; MTX: methotrexate; PR3-ANCA: proteinase 3-anti-neutrophil cytoplasmic antibody; PSL: prednisolone; PTU: propylthiouracil; RI (13mCi): radioisotope (13mCi); TSH: thyroid-stimulating hormone.
Liu et al., "U-shaped association between serum free triiodothyronine and recurrence of atrial fibrillation after catheter ablation," Journal of Interventional Cardiac Electrophysiology, vol.
Hormonal indices Study subject with osteoporosis Free thyroxine (pmol/L) 33.12 (21.80) Free triiodothyronine (pmol/L) 12.72 (8.51) Thyroid-stimulating 0.25 (0.03) hormone ([micro]/U/ml) Osteocalcin (ng/ml) 52.79 (15.62) 25-Hydroxyvitamin D (nmol/l) 53.60 (15.77) Parathyroid hormone (pmol/L) 5.43 (5.85) Hormonal indices Study subjects p value without osteoporosis Free thyroxine (pmol/L) 27.64 (24.40) 0.4 Free triiodothyronine (pmol/L) 7.81 (6.91) 0.02 * Thyroid-stimulating 0.41 (0.25) 0.006 * hormone ([micro]/U/ml) Osteocalcin (ng/ml) 29.85 (20.56) 0.000 * 25-Hydroxyvitamin D (nmol/l) 66.78 (16.25) 0.05 Parathyroid hormone (pmol/L) 5.57 (0.93) 0.90 * Significant p values.
At two months, mean values for free thyroxine and free triiodothyronine had decreased to a significantly greater extent, and the mean TSH value had increased to a significantly greater extent, in the selenium group than in the control group.
Fasting plasma insulin (FINS) concentration, serum level of thyroid-stimulating hormone (TSH), free triiodothyronine (FT3) concentration, free tetraiodothyronine (FT4) concentration, and thyroid peroxidase antibody (TPOAB) concentration were measured by electrochemiluminescence analyzer (Roche Diagnostics, Basel, Switzerland).
ALAT, alanine aminotransferase; ASAT, aspartate aminotransferase; BMI, body mass index; CRP, C-reactive protein; FT3, free triiodothyronine; FT4, free thyroxine; HbA1c, hemoglobin A1c; HDL, high-density lipoprotein; HOMA-IR, homeostasis model assessment-estimated insulin resistance; LDL, low-density lipoprotein; NM, not measured; TG, triglycerides; TSH, thyroid-stimulating hormone.
Serum thyroid-stimulating hormone (TSH) was 1.35 |iIU/mL (normal range: 0.35-4.94 [micro]IU/mL), free triiodothyronine (FT3) was 2.87pg/mL (normal range: 1.71-3.71 pg/mL), free thyroxine (FT4) was 1.43 ng/dL (normal range: 0.70-1.48 ng/dL), and thyroglobulin was 12.93 ng/mL (normal range: 0-32.7 ng/mL).
Serum insulin-like growth factor-1 and insulin-like growth factor-binding protein 3 levels were low, but free triiodothyronine, free thyroxine, and adrenocorticotropic hormone levels were almost normal.
Thyroid function tests were consistent with a hyperfunctioning thyroid state: thyrotropin (TSH) < 0,005 IU/mL (normal range 0,358-3,740 IU/mL), free thyroxine (fT4) 4,97 ng/ dL (normal range 0,76-1,46 ng/dL), free triiodothyronine (fT3) 27,58 pg/mL (normal range 2,18-3,98 pg/mL), with positive anti-thyroid autoantibodies: thyroid peroxidase antibodies (anti-TPO) > 3340 IU/mL (normal range 0-100 IU/ mL), thyroglobulin antibodies (anti-Tg) > 24400 IU/mL (normal range 0-344 IU/mL), and thyrotropin receptor antibodies (TRAbs) 14,3 IU/mL (normal range < 1,2 IU/mL).
[20] Higher free triiodothyronine levels may be one of the cause for high PP in overweight and obese adult individuals.