Search results
Results From The WOW.Com Content Network
T 3 is the more metabolically active hormone produced from T 4.T 4 is deiodinated by three deiodinase enzymes to produce the more-active triiodothyronine: . Type I present in liver, kidney, thyroid, and (to a lesser extent) pituitary; it accounts for 80% of the deiodination of T 4.
The major form of thyroid hormone in the blood is thyroxine (T 4), whose half-life of around one week [4] is longer than that of T 3. [5] In humans, the ratio of T 4 to T 3 released into the blood is approximately 14:1. [6] T 4 is converted to the active T 3 (three to four times more potent than T 4) within cells by deiodinases (5′-deiodinase).
Low-T3 syndrome and high-T3 syndrome: Consequences of step-up hypodeiodination, e.g. in critical illness as an example for type 1 allostasis, [20] or hyperdeiodination, as in type 2 allostasis, including posttraumatic stress disorder. [12] Resistance to thyroid hormone: Feedback loop interrupted on the level of pituitary thyroid hormone receptors.
Euthyroid sick syndrome ( ESS) is a state of adaptation or dysregulation of thyrotropic feedback control [ 1] wherein the levels of T3 and/or T4 are abnormal, but the thyroid gland does not appear to be dysfunctional. This condition may result from allostatic responses of hypothalamus-pituitary-thyroid feedback control, dyshomeostatic disorders ...
Also, iodothyronine deiodinases (type 2 y 3; DIO2 and DIO3, respectively) respond to seasonal changes in photoperiod-driven melatonin secretion and govern peri-hypothalamic catabolism of the prohormone thyroxine (T4). In long summer days, the production of hypothalamic T3 increase due to DIO-2-mediated conversion of T4 to the biologically ...
The hypothalamus ( pl.: hypothalami; from Ancient Greek ὑπό (hupó) 'under' and θάλαμος (thálamos) 'chamber') is a small part of the vertebrate brain that contains a number of nuclei with a variety of functions. One of the most important functions is to link the nervous system to the endocrine system via the pituitary gland.
003444. [ edit on Wikidata] Thyroid function tests ( TFTs) is a collective term for blood tests used to check the function of the thyroid. [ 1] TFTs may be requested if a patient is thought to suffer from hyperthyroidism (overactive thyroid) or hypothyroidism (underactive thyroid), or to monitor the effectiveness of either thyroid-suppression ...
Thyroid disease is a medical condition that affects the function of the thyroid gland. The thyroid gland is located at the front of the neck and produces thyroid hormones [ 1] that travel through the blood to help regulate many other organs, meaning that it is an endocrine organ. These hormones normally act in the body to regulate energy use ...