Is sodium iodine a Symporter?
The sodium-iodide symporter is most highly expressed in thyroid epithelial cells. Lower levels of expression can be detected in mammary gland, salivary gland, stomach and colon, but none of these tissues is known to organify iodide.
Where is sodium iodide Symporter found?
The human sodium iodide symporter (hNIS) gene is naturally present in humans with fairly restricted tissue expression (thyroid, stomach, salivary, and lactating mammary glands).
What is Organification thyroid hormone?
Organification is a biochemical process that takes place in thyroid gland. It is the incorporation of iodine into thyroglobulin for the production of thyroid hormone, a step done after the oxidation of iodide by the enzyme thyroid peroxidase (TPO).
What is the function of sodium iodide Symporter?
The sodium/iodide symporter (NIS or SLC5A5) is an intrinsic membrane protein implicated in iodide uptake into thyroid follicular cells. It plays a crucial role in iodine metabolism and thyroid regulation and its function is widely exploited in the diagnosis and treatment of benign and malignant thyroid diseases.
What is iodide organification defect?
Defective organification of iodine is due to abnormalities of Tg and TPO synthesis or H2O2 production. Organification defect in iodine caused by abnormal H2O2 production is rare, so abnormal Tg and TPO synthesis is thought to be the major cause of defective organification of iodine.
What is sodium iodide?
What is sodium iodide? Sodium iodide is an iodide salt that is formed into an injectable medicine. Sodium iodide is used to treat or prevent iodine deficiency caused by poor nutrition or poor absorption by the body. Sodium iodide may also be used to treat a thyroid disorder.
Is sodium iodide harmful?
May cause respiratory and digestive tract irritation. May cause eye and skin irritation. Prolonged exposure may cause pulmonary edema. This substance has caused adverse reproductive and fetal effects in animals.
Is a symporter active transport?
Symporters and antiporters are involved in active transport. Antiporters transport molecules in opposite directions, while symporters transport molecules in the same direction.
What is the function of the sodium iodide symporter?
The sodium-iodide symporter (NIS) is an intrinsic plasma membrane protein that mediates active transport of iodide in the thyroid gland and several other extra-thyroidal tissues. This activity has been utilized for many years for imaging the thyroid gland and for treatment of thyroid disease both be …
What is the role of the Na+/I-symporter in thyroid hormone synthesis?
Iodide concentration by the thyroid gland, an essential step for thyroid hormone synthesis, is mediated by the Na+/I- symporter (NIS). To identify factors that may regulate this process, we have studied NIS gene expression in the Fisher rat thyroid cell line (FRTL-5) by a semi-quantitative reverse t …
What is the function of the Na+ I− symporter?
Iodide (I−), an essential constituent of the THs, is actively transported into the thyroid via the Na+/I−symporter (NIS), a key plasma membrane glycoprotein. The ability of the thyroid to accumulate I−was first described by Baumann in 1896 (1, 2).
What causes iodide transport defects and congenital hypothyroidism?
Pohlenz J, Refetoff S. Mutations in the sodium/iodide symporter (NIS) gene as a cause for iodide transport defects and congenital hypothyroidism. Biochimie. 1999;81:469–76.