Search results
Results from the WOW.Com Content Network
Levothyroxine is the chemical name of the manufactured version of T 4, which is metabolised more slowly than T 3 and hence usually only needs once-daily administration. Natural desiccated thyroid hormones are derived from pig thyroid glands, and are a "natural" hypothyroid treatment containing 20% T 3 and traces of T 2 , T 1 and calcitonin .
At the cellular level, T 3 is the body's more active and potent thyroid hormone. [2] T 3 helps deliver oxygen and energy to all of the body's cells, its effects on target tissues being roughly four times more potent than those of T 4. [2] Of the thyroid hormone that is produced, just about 20% is T 3, whereas 80% is produced as T 4.
As its name suggests, it depends upon the hypothalamus, the pituitary gland, and the thyroid gland. The hypothalamus senses low circulating levels of thyroid hormone (Triiodothyronine (T3) and Thyroxine (T4)) and responds by releasing thyrotropin-releasing hormone (TRH). The TRH stimulates the anterior pituitary to produce thyroid-stimulating ...
Thyroid-stimulating hormone (also known as thyrotropin, thyrotropic hormone, or abbreviated TSH) is a pituitary hormone that stimulates the thyroid gland to produce thyroxine (T 4), and then triiodothyronine (T 3) which stimulates the metabolism of almost every tissue in the body. [1]
The hypothalamus, pancreas, and thymus also function as endocrine glands, among other functions. (The hypothalamus and pituitary glands are organs of the neuroendocrine system . One of the most important functions of the hypothalamus—it is located in the brain adjacent to the pituitary gland—is to link the endocrine system to the nervous ...
In vertebrate biology, iodine's primary function is as a constituent of the thyroid hormones, thyroxine (T4) and triiodothyronine (T3). These molecules are made from addition-condensation products of the amino acid tyrosine, and are stored prior to release in an iodine-containing protein called thyroglobulin.
When circulating in the body, T3 and T4 are bound to transport proteins. Only a small fraction of the circulating thyroid hormones are unbound or free, and thus biologically active. T3 and T4 levels can thus be measured as free T3 and T4, or total T3 and T4, which takes into consideration the free hormones in addition to the protein-bound hormones.
Thyroxine-binding globulin (TBG) is a globulin protein encoded by the SERPINA7 gene in humans. TBG binds thyroid hormones in circulation.It is one of three transport proteins (along with transthyretin and serum albumin) responsible for carrying the thyroid hormones thyroxine (T 4) and triiodothyronine (T 3) in the bloodstream.