monoiodotyrosine and Hyperthyroidism

Topics: Diiodothyronines; Humans; Hyperthyroidism; Hypothyroidism; Infant, Newborn; Monoiodotyrosine

Normal serum monoiodotyrosine (MIT) levels (n = 152) were 0.69 +/- 0.20 nmol/l. There was wide variation of MIT levels in a 24-hour period without diurnal pattern, and there was no change throughout the menstrual cycle. MIT levels declined upon aging, but levels in hypo- and hyperthyroidism were not significantly different. MIT levels were detected in athyrotic patients (0.32 +/- 0.08 nmol/l). Desiccated thyroid raised the athyrotic MIT levels to the normal range, while levothyroxine did not. Diiodotyrosine (DIT) infusion caused an MIT rise which paralleled but lagged 1 h behind the DIT rise. These data suggest thyroidal as well as nonthyroidal sources of MIT, one of which is deiodination of DIT. Ingestion of 1 g MIT increased serum MIT to 10.6 +/- 1.7 mumol/l in women, and 7.1 +/- 2.3 mumol/l in men 30 min after ingestion; the serum half-life was 45 min.

Topics: Adult; Aging; Circadian Rhythm; Diiodotyrosine; Female; Humans; Hyperthyroidism; Hypothyroidism; Male; Menstrual Cycle; Middle Aged; Monoiodotyrosine; Reference Values; Thyroxine

In homogenate supernatants of kidneys of male rats the extent of deiodination of L-diiodotyrosine (L-DJT) and L-thyroxine (L-T4) was investigated in dependence on the thyroid function (hypo- and hyperthyroidized) and also in dependence on age. In rats hypothyroidized by loading with Methylthiouracil (MTU) or Methimazol (MMI) the deiodination for L-DJT and L-T4 was significantly reduced, in rats loaded with 40 mug T4 sc. for 10 days, the deiodination was significantly enhanced compared with untreated control animals. With advancing age (6 weeks, 3 or 12 month) the deiodination activity is highly significantly reduced. The results underline relations between thyroid gland function and deiodination activity in kidney.

Topics: Age Factors; Animals; Diiodotyrosine; Hyperthyroidism; Hypothyroidism; Iodine; Kidney; Male; Methimazole; Methylthiouracil; Monoiodotyrosine; Rats; Thyroid Diseases; Thyroid Hormones; Thyroxine; Triiodothyronine

Topics: Animals; Body Weight; Diet; Hyperthyroidism; Iodine; Iodine Radioisotopes; Monoiodotyrosine; Pituitary Gland; Rats; Thyroid Gland; Thyroidectomy; Thyrotropin; Thyrotropin-Releasing Hormone; Thyroxine; Triiodothyronine

Topics: Adsorption; Animals; Binding, Competitive; Cattle; Charcoal; Diiodotyrosine; Humans; Hyperthyroidism; Hypothyroidism; Iodine Isotopes; Methods; Monoiodotyrosine; Rabbits; Radioimmunoassay; Sodium Salicylate; Swine; Thyroglobulin; Thyroxine; Thyroxine-Binding Proteins; Triiodothyronine

Topics: Animals; Anxiety; Female; Humans; Hyperthyroidism; Kidney; Liver; Lung; Male; Monoiodotyrosine; Muscles; Myocardium; Peroxidases; Rabbits

Topics: Amino Acids; Animals; Anxiety; Chromatography, Paper; Diiodotyrosine; Female; Humans; Hyperthyroidism; Iodine Isotopes; Male; Monoiodotyrosine; Rabbits; Thyroid Gland; Thyronines; Thyroxine; Triiodothyronine

Topics: Blood Protein Electrophoresis; Blood Proteins; Centrifugation, Density Gradient; Chromatography, Gel; Chromatography, Ion Exchange; Electrophoresis, Paper; Humans; Hyperthyroidism; Immunoelectrophoresis; Iodine; Iodine Radioisotopes; Iodoproteins; Monoiodotyrosine; Protein Binding; Serum Albumin, Radio-Iodinated; Thyroglobulin; Thyroid Neoplasms; Thyroxine; Thyroxine-Binding Proteins

Topics: Chemistry, Clinical; Chromatography, Gel; Chromatography, Paper; Diiodotyrosine; Humans; Hyperthyroidism; Iodine Isotopes; Methods; Monoiodotyrosine; Thyroxine; Triiodothyronine

Topics: Diiodotyrosine; Humans; Hyperthyroidism; In Vitro Techniques; Iodine Radioisotopes; Keto Acids; Monoiodotyrosine; Thyroid Gland; Thyroid Hormones; Tyrosine

Topics: Diiodotyrosine; Graves Disease; Humans; Hyperthyroidism; Male; Middle Aged; Monoiodotyrosine; Thyroid Gland; Thyroid Hormones; Thyronines; Thyroxine; Triiodothyronine

Topics: Adenocarcinoma; Colloids; Humans; Hyperthyroidism; Hypothyroidism; Iodine; Iodine Isotopes; Iodine Radioisotopes; Iodoproteins; Liver; Monoiodotyrosine; Neoplasm Metastasis; Proteins; Serum Albumin, Radio-Iodinated; Thyroglobulin; Thyroid Neoplasms; Thyroidectomy; Thyrotropin; Thyroxine; Triiodothyronine

Topics: Chromatography, Ion Exchange; Diiodotyrosine; Humans; Hyperthyroidism; Iodine Isotopes; Methods; Monoiodotyrosine; Radioisotope Dilution Technique; Thyroid Hormones; Tyrosine

Topics: Animals; Chromatography, Gel; Chromatography, Ion Exchange; Dogs; Femoral Artery; Femoral Vein; Hyperthyroidism; Iodine Isotopes; Monoiodotyrosine; Thyroid Gland; Thyroid Hormones; Thyrotropin; Tyrosine

Topics: Blood Chemical Analysis; Chromatography; Geriatrics; Goiter; Hyperthyroidism; Iodine Isotopes; Monoiodotyrosine; Myxedema; Neoplasms; Propylthiouracil; Thiourea; Thyronines; Thyroxine; Tyrosine

Topics: Diabetes Mellitus; Endocrine System Diseases; Humans; Hyperthyroidism; Metabolic Diseases; Monoiodotyrosine; Thyroxine