AnatomyDiseasesChemicals and DrugsAnalytical, Diagnostic and Therapeutic Techniques and EquipmentPhenomena and Processes
Thyroxine-Binding ProteinsThyroxineThyroid Function TestsTriiodothyronineHyperthyroxinemiaPrealbuminSex Hormone-Binding GlobulinTranscortinTriiodothyronine, ReverseThyroid HormonesGlobulinsGonadal Steroid HormonesSerum GlobulinsThyroxine-Binding GlobulinTestosteroneThyrotropinHypothyroidismThyroid GlandRadioimmunoassayEstradiolDehydroepiandrosterone SulfateDehydroepiandrosterone11-HydroxycorticosteroidsKwashiorkorAndrogensHyperthyroidismEstroneMenopausePostmenopausegamma-GlobulinsPremenopauseIodide PeroxidaseAndrostenedioneHormonesIodine IsotopesHydrocortisone
TriiodothyronineProteinProteinsTransthyretin and albuminPrealbuminSerumAlbuminImmunoglobulinsDeficiencyHormoneHormonesLiverUptakeHighFreeHumanApproximatelyActivityConcentrationSitesHormone-bindingConcentrationsTetraiodothyronineDecreaseGeneTransport proteinPatient'sCarriesHumansEndogenousEquilibriumTotalResinCirculationNuclear
Triiodothyronine5
Protein6
  • Thyroxine-binding globulin (TBG) is a globulin protein that in humans is encoded by the SERPINA7 gene. (wikipedia.org)
  • Because TBG accounts for 76% of plasma protein thyroxine-binding activity, an increase or decrease in its circulating level alters total concentrations of T4 and T3 in blood, leading to potential confusion with true thyroid gland dysfunction. (selfdecodelabs.com)
  • The primary transport protein is thyroxine-binding globulin (TBG), which has high affinity but low capacity for T3 and T4. (msdmanuals.com)
  • When thyroid hormones are secreted from your thyroid gland, they are bound to a carrier, a protein. (synergyfixme.com)
  • This protein is called "thyroxine-binding globulin" or TBG. (synergyfixme.com)
  • Hypothyroidism is one of the most important complications which occur due to urinary loss of protein bound thyroid hormones, such as thyroxin binding globulin, transthyretin and albumin. (bvsalud.org)
Proteins6
  • Of these three proteins, TBG has the highest affinity for T4 and T3 but is present in the lowest concentration relative to transthyretin and albumin, which also bind T3 and T4 in circulation. (wikipedia.org)
  • T3 in cell cytoplasm and T3 generated from T4 within the cell diffuse into the nucleus and bind to thyroid receptor proteins, which appear to be primarily attached to DNA. (pediatriconcall.com)
  • Receptor binding leads to activation or repression of DNA transcription, thereby altering the amounts of mRNA and resultant proteins. (pediatriconcall.com)
  • Most of the circulating testosterone is bound to carrier proteins (SHBG = sex hormone-binding globulin). (cdc.gov)
  • Free T3 and T4 are then released into the bloodstream, where they are bound to serum proteins for transport. (msdmanuals.com)
  • In many tissues the activity of testosterone appears to depend on reduction to dihydrotestosterone, which binds to cytosol receptor proteins. (nih.gov)
Transthyretin and albumin1
  • Unlike transthyretin and albumin, TBG has a single binding site for T4/T3. (wikipedia.org)
Prealbumin1
Serum5
  • A minor proportion of the THs is bound on serum lipoproteins. (medscape.com)
  • Estrogen, Oral Contraceptives: Estrogens tend to increase serum thyroxine -binding globulin (TBg). (pediatriconcall.com)
  • To address this, concentrations of testosterone, sex hormone binding globulin, androstanediol glucuronide (a metabolite of dihydrotestosterone) and estradiol were measured in stored serum specimens from men examined in the morning sample of the first phase of NHANES III (1988-1991). (cdc.gov)
  • Approximately 0.3% of total serum T3 and 0.03% of total serum T4 are free and in equilibrium with bound hormones. (msdmanuals.com)
  • Glycoprotein found in alpha(1)-globulin region in human serum. (lookformedical.com)
Albumin1
  • the converse is true, ie, high capacity but low avidity, for TH binding to TTR and albumin. (medscape.com)
Immunoglobulins1
  • Very rarely, and in the context of anti-TH antibodies in autoimmune thyroid disease, immunoglobulins also may bind TH. (medscape.com)
Deficiency1
  • Thyroxine-binding globulin (TBG) deficiency is a benign condition that is either acquired or inherited. (medscape.com)
Hormone15
  • Thyroxine-binding globulin tests are sometimes used to find the cause of raised or lowered levels of thyroid hormone. (wikipedia.org)
  • This is done by measuring resin binding to labeled thyroid hormone, which happens only when the labeled thyroid hormone is free. (wikipedia.org)
  • So, for instance, if the patient is truly hypothyroid, and TBG levels are normal, then there are many sites open for binding on the TBG, since the total thyroid hormone level is low. (wikipedia.org)
  • Therefore, when the labeled hormone is added, it will bind mostly to the TBG, leaving little of it left for binding to the resin. (wikipedia.org)
  • In contrast, however, if the patient is truly hyperthyroid, and TBG levels are normal, the patient's endogenous hormone will saturate the TBG binding sites more, leaving less room for the labeled hormone, which allows greater binding to the resin. (wikipedia.org)
  • If, for example, the TBG level is high, which can occur when estrogen levels are high, the TBG will bind more thyroid hormone, decreasing the free hormone available in the blood, which leads to stimulation of TSH, and the production of more thyroid hormone. (wikipedia.org)
  • And so, when labeled hormone is added, since TBG is so high, once equilibrium between the binding of endogenous thyroid hormone and the labeled hormone is achieved, less free labeled hormone will be available for uptake into the resin. (wikipedia.org)
  • On the converse, in the presence of corticosteroids, which lower TBG levels, the total thyroid hormone (bound and free) in the blood will be low. (wikipedia.org)
  • Thus, when the labeled hormone is added, since so little TBG is available in the blood, after equilibrium is achieved, only a small portion of it will bind, leaving plenty available for uptake by the resin. (wikipedia.org)
  • T3 binding to the thyroid hormone receptor (TR), changes the conformation of the TR, allowing it to bind to the retinoid X receptor (RXR) and form a coactivator complex. (drugbank.com)
  • T4 is converted (in most tissues) to T3, the active form that binds to nuclear receptors, and to reverse T3 (rT3), an inactive form of thyroid hormone without metabolic activity. (msdmanuals.com)
  • Generally, the amount of this sex-hormone binding globulin in the plasma will determine the distribution of testosterone between free and bound forms, and the free testosterone concentration will determine its half-life. (nih.gov)
  • In cases of high TBG, more thyroid hormone will be bound, decreasing free hormone in the blood. (medscape.com)
  • At the pituitary, TRH binds to receptors in thyrotroph cells causing the production and secretion of thyroid stimulating hormone (TSH), also known as thyrotropin. (ascls.org)
  • Thyroid stimulating hormone binds to TSH receptors in the follicular cells of the thyroid gland causing the production and secretion of thyroid hormones, T 3 and T 4 . (ascls.org)
Hormones4
Liver1
  • Thyroxine-binding globulin (TBG) is a 395-amino acid, 54kd polypeptide that is synthesized in the liver and encoded by a single gene copy. (medscape.com)
Uptake1
  • It will show that, actually, the T3 Uptake is low when the thyroid binding globulin, or TBGs are high. (synergyfixme.com)
High1
Free1
  • Testosterone in plasma is 98 percent bound to a specific testosterone-estradiol binding globulin, and about 2 percent is free. (nih.gov)
Human1
Approximately1
  • Twenty-five mcg of liothyronine is equivalent to approximately 1 grain of desiccated thyroid or thyroglobulin and 0.1 mg of L-thyroxine. (rxlist.com)
Activity1
  • Thyroid extract is dried and powdered thyroid glands from pigs containing tiiodothyronine (T3) and thyroxine (T4) used to supplement low or absent thyroid activity. (drugbank.com)
Concentration1
  • The binding sites of the labeled antibody become occupied partly by the sample analyte (depending on its concentration) and partly by the ruthenium-labeled hapten to form the respective immunocomplexes. (cdc.gov)
Sites1
  • Endogenous testosterone released from the sample by ANS (8-anilino-1-naphthalene sulfonic acid) and norgestrel competes with the added testosterone derivative labeled with ruthenium complex for the binding sites on the biotinylated antibody. (cdc.gov)
Hormone-binding4
  • To address this, concentrations of testosterone, sex hormone binding globulin, androstanediol glucuronide (a metabolite of dihydrotestosterone) and estradiol were measured in stored serum specimens from men examined in the morning sample of the first phase of NHANES III (1988-1991). (cdc.gov)
  • Most of the circulating testosterone is bound to carrier proteins (SHBG = sex hormone-binding globulin). (cdc.gov)
  • Following oral administration, norethindrone is 36% bound to sex hormone-binding globulin (SHBG) and 61% bound to albumin. (drugs.com)
  • 80% bound to sex-hormone binding globulin. (concentrexlabs.com)
Concentrations1
Tetraiodothyronine1
  • Levothyroxine sodium is the monosodium salt of the levorotatory isomer of thyroxin (tetraiodothyronine), the principal hormone secreted by the normal thyroid gland. (rxmed.com)
Decrease1
  • 6 ) In rodents, inflammation leads to a significant decrease in transthyretin, which is the major plasma thyroid hormone binding-protein in that species. (chriskresser.com)
Gene3
  • Thyroxine-binding globulin (TBG) is a globulin protein that in humans is encoded by the SERPINA7 gene. (wikipedia.org)
  • Thyroxine-binding globulin (TBG) is a 395-amino acid, 54kd polypeptide that is synthesized in the liver and encoded by a single gene copy. (medscape.com)
  • The endoplasmic reticulum (ER)-anchored protein, insulin-induced gene (Insig), retains the sterol regulatory element-binding protein (SREBP)-SREBP cleavage-activating protein (SCAP) complex in the ER, negatively affecting SREBP activation and lipogenesis in the liver [ 9 ]. (biomedcentral.com)
Transport protein1
Patient's1
  • In contrast, however, if the patient is truly hyperthyroid, and TBG levels are normal, the patient's endogenous hormone will saturate the TBG binding sites more, leaving less room for the labeled hormone, which allows greater binding to the resin. (wikipedia.org)
Carries1
Humans1
  • TBG is the major binding protein in humans, and under normal circumstances, less than 0.05 percent of thyroid hormone is unbound ("free") in the blood. (chriskresser.com)
Endogenous1
  • Endogenous testosterone released from the sample by ANS (8-anilino-1-naphthalene sulfonic acid) and norgestrel competes with the added testosterone derivative labeled with ruthenium complex for the binding sites on the biotinylated antibody. (cdc.gov)
Equilibrium1
  • About 0.3% of total serum T3 and 0.03% of total serum T4 are free and in equilibrium with bound hormones. (msdmanuals.com)
Total3
  • So, for instance, if the patient is truly hypothyroid, and TBG levels are normal, then there are many sites open for binding on the TBG, since the total thyroid hormone level is low. (wikipedia.org)
  • On the converse, in the presence of corticosteroids, which lower TBG levels, the total thyroid hormone (bound and free) in the blood will be low. (wikipedia.org)
  • We also measured free thyroxine (T 4 ), total T 4 , and thyroid-stimulating hormone (TSH) in women during pregnancy, and TSH in neonates. (cdc.gov)
Resin2
  • This is done by measuring resin binding to labeled thyroid hormone, which happens only when the labeled thyroid hormone is free. (wikipedia.org)
  • Therefore, when the labeled hormone is added, it will bind mostly to the TBG, leaving little of it left for binding to the resin. (wikipedia.org)
Circulation1
Nuclear1
  • Potential cis-acting transcriptional regulatory elements including a TATA box, a CAAT box, and a hepatocyte nuclear factor-1 binding motif were identified in the upstream region. (nih.gov)