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Thyrotropin
Thyroid-stimulating hormone (also known as thyrotropin, thyrotropic hormone, or abbreviated TSH) is a pituitary hormone that stimulates the thyroid gland to produce thyroxine (T4), and then triiodothyronine (T3) which stimulates the metabolism of almost every tissue in the body. It is a glycoprotein hormone produced by thyrotrope cells in the anterior pituitary gland, which regulates the endocrine function of the thyroid. Physiology Hormone levels TSH (with a half-life of about an hour) stimulates the thyroid gland to secrete the hormone thyroxine (T4), which has only a slight effect on metabolism. T4 is converted to triiodothyronine (T3), which is the active hormone that stimulates metabolism. About 80% of this conversion is in the liver and other organs, and 20% in the thyroid itself. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thyrotropin-releasing Hormone
Thyrotropin-releasing hormone (TRH) is a hypophysiotropic hormone produced by neurons in the hypothalamus that stimulates the release of thyroid-stimulating hormone (TSH) and prolactin from the anterior pituitary. TRH has been used clinically for the treatment of spinocerebellar degeneration and disturbance of consciousness in humans. Its pharmaceutical form is called protirelin (INN) (). Synthesis and release TRH is synthesized within parvocellular neurons of the paraventricular nucleus of the hypothalamus. It is translated as a 242-amino acid precursor polypeptide that contains 6 copies of the sequence -Gln-His-Pro-Gly-, flanked by Lys-Arg or Arg-Arg sequences. To produce the mature form, a series of enzymes are required. First, a protease cleaves to the C-terminal side of the flanking Lys-Arg or Arg-Arg. Second, a carboxypeptidase removes the Lys/Arg residues leaving Gly as the C-terminal residue. Then, this Gly is converted into an amide residue by a series of enzy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pulsatile Secretion
Pulsatile secretion is a biochemical phenomenon observed in a wide variety of cell and tissue types, in which chemical products are secreted in a regular temporal pattern. The most common cellular products observed to be released in this manner are intercellular signaling molecules such as hormones or neurotransmitters. Examples of hormones that are secreted pulsatilely include insulin, thyrotropin, TRH, gonadotropin-releasing hormone (GnRH) and growth hormone (GH). In the nervous system, pulsatility is observed in oscillatory activity from central pattern generators. In the heart, pacemakers are able to work and secrete in a pulsatile manner. A pulsatile secretion pattern is critical to the function of many hormones in order to maintain the delicate homeostatic balance necessary for essential life processes, such as development and reproduction. Variations of the concentration in a certain frequency can be critical to hormone function, as evidenced by the case of GnRH agoni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TSHB
Thyroid stimulating hormone, beta also known as TSHB is a protein which in humans is encoded by the ''TSHB'' gene. Function Thyrotropin-stimulating hormone (TSH) is a noncovalently linked glycoprotein heterodimer and is part of a family of pituitary hormones containing a common alpha subunit ( TSHA) and a unique beta subunit (this protein) that confers specificity. See also * thyroid stimulating hormone Thyroid-stimulating hormone (also known as thyrotropin, thyrotropic hormone, or abbreviated TSH) is a pituitary hormone that stimulates the thyroid gland to produce thyroxine (T4), and then triiodothyronine (T3) which stimulates the metabolism of ... References Further reading * * * * * * * * * * * * * * * * * * * * {{gene-1-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thyroid System
The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thyroid is located at the front of the neck, below the Adam's apple. Microscopically, the functional unit of the thyroid gland is the spherical thyroid follicle, lined with follicular cells (thyrocytes), and occasional parafollicular cells that surround a lumen containing colloid. The thyroid gland secretes three hormones: the two thyroid hormones triiodothyronine (T3) and thyroxine (T4)and a peptide hormone, calcitonin. The thyroid hormones influence the metabolic rate and protein synthesis, and in children, growth and development. Calcitonin plays a role in calcium homeostasis. Secretion of the two thyroid hormones is regulated by thyroid-stimulating hormone (TSH), which is secreted from the anterior pituitary gland. TSH is regulated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thyroid
The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thyroid is located at the front of the neck, below the Adam's apple. Microscopically, the functional unit of the thyroid gland is the spherical thyroid follicle, lined with follicular cells (thyrocytes), and occasional parafollicular cells that surround a lumen containing colloid. The thyroid gland secretes three hormones: the two thyroid hormones triiodothyronine (T3) and thyroxine (T4)and a peptide hormone, calcitonin. The thyroid hormones influence the metabolic rate and protein synthesis, and in children, growth and development. Calcitonin plays a role in calcium homeostasis. Secretion of the two thyroid hormones is regulated by thyroid-stimulating hormone (TSH), which is secreted from the anterior pituitary gland. TSH is regula ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypothyroidism
Hypothyroidism (also called ''underactive thyroid'', ''low thyroid'' or ''hypothyreosis'') is a disorder of the endocrine system in which the thyroid gland does not produce enough thyroid hormone. It can cause a number of symptoms, such as poor ability to tolerate cold, a feeling of tiredness, constipation, slow heart rate, depression, and weight gain. Occasionally there may be swelling of the front part of the neck due to goiter. Untreated cases of hypothyroidism during pregnancy can lead to delays in growth and intellectual development in the baby or congenital iodine deficiency syndrome. Worldwide, too little iodine in the diet is the most common cause of hypothyroidism. Hashimoto's thyroiditis is the most common cause of hypothyroidism in countries with sufficient dietary iodine. Less common causes include previous treatment with radioactive iodine, injury to the hypothalamus or the anterior pituitary gland, certain medications, a lack of a functioning thyroid at bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypothalamus
The hypothalamus () is a part of the brain that contains a number of small 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. The hypothalamus is located below the thalamus and is part of the limbic system. In the terminology of neuroanatomy, it forms the ventral part of the diencephalon. All vertebrate brains contain a hypothalamus. In humans, it is the size of an almond. The hypothalamus is responsible for regulating certain metabolic processes and other activities of the autonomic nervous system. It synthesizes and secretes certain neurohormones, called releasing hormones or hypothalamic hormones, and these in turn stimulate or inhibit the secretion of hormones from the pituitary gland. The hypothalamus controls body temperature, hunger, important aspects of parenting and maternal attachment behaviours, thirst, fatigue, sleep, and circadian rhythms. Structure T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chorionic Gonadotropin Alpha
Glycoprotein hormones, alpha polypeptide is a protein that in humans is encoded by the ''CGA'' gene. The gonadotropin hormones, human chorionic gonadotropin (hCG), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and thyroid-stimulating hormone (TSH) are heterodimers consisting of alpha and beta subunits (also called chains) that are associated non-covalently. The alpha subunits of these four human glycoprotein hormones Gonadotropins are glycoprotein hormones secreted by gonadotropic cells of the anterior pituitary of vertebrates. This family includes the mammalian hormones follicle-stimulating hormone (FSH) and luteinizing hormone (LH), the placental/chorionic ... are identical; however, their beta chains are unique and confer biological specificity. The protein encoded by this gene is the alpha subunit and belongs to the glycoprotein hormones alpha chain family. References Further reading * * * * * * * * * * * * * * * * * * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chorionic Gonadotropin Alpha
Glycoprotein hormones, alpha polypeptide is a protein that in humans is encoded by the ''CGA'' gene. The gonadotropin hormones, human chorionic gonadotropin (hCG), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and thyroid-stimulating hormone (TSH) are heterodimers consisting of alpha and beta subunits (also called chains) that are associated non-covalently. The alpha subunits of these four human glycoprotein hormones Gonadotropins are glycoprotein hormones secreted by gonadotropic cells of the anterior pituitary of vertebrates. This family includes the mammalian hormones follicle-stimulating hormone (FSH) and luteinizing hormone (LH), the placental/chorionic ... are identical; however, their beta chains are unique and confer biological specificity. The protein encoded by this gene is the alpha subunit and belongs to the glycoprotein hormones alpha chain family. References Further reading * * * * * * * * * * * * * * * * * * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Subunit Of Glycoprotein Hormones
Glycoprotein hormones, alpha polypeptide is a protein that in humans is encoded by the ''CGA'' gene. The gonadotropin hormones, human chorionic gonadotropin (hCG), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and thyroid-stimulating hormone (TSH) are heterodimers consisting of alpha and beta subunits (also called chains) that are associated non-covalently. The alpha subunits of these four human glycoprotein hormones Gonadotropins are glycoprotein hormones secreted by gonadotropic cells of the anterior pituitary of vertebrates. This family includes the mammalian hormones follicle-stimulating hormone (FSH) and luteinizing hormone (LH), the placental/chorionic ... are identical; however, their beta chains are unique and confer biological specificity. The protein encoded by this gene is the alpha subunit and belongs to the glycoprotein hormones alpha chain family. References Further reading * * * * * * * * * * * * * * * * * * { ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium-iodide Symporter
The sodium/iodide cotransporter, also known as the sodium/iodide symporter (NIS), is a protein that in humans is encoded by the ''SLC5A5'' gene. It is a transmembrane glycoprotein with a molecular weight of 87 kAtomic mass unit, Da and 13 transmembrane domains, which transports two sodium cations (Na+) for each iodide anion (I−) into the cell. NIS mediated uptake of iodide into Thyroid epithelial cell, follicular cells of the thyroid gland is the first step in the synthesis of thyroid hormone. Iodine uptake Iodine uptake mediated by thyroid Thyroid epithelial cell, follicular cells from the blood plasma is the first step for the synthesis of thyroid hormones. This ingested iodine is bound to serum proteins, especially to albumins. The rest of the iodine which remains unlinked and free in bloodstream, is removed from the body through urine (the kidney is essential in the removal of iodine from extracellular space). Iodine uptake is a result of an active transport mechanism media ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperthyroidism
Hyperthyroidism is the condition that occurs due to excessive production of thyroid hormones by the thyroid gland. Thyrotoxicosis is the condition that occurs due to excessive thyroid hormone of any cause and therefore includes hyperthyroidism. Some, however, use the terms interchangeably. Signs and symptoms vary between people and may include irritability, muscle weakness, sleeping problems, a fast heartbeat, heat intolerance, diarrhea, enlargement of the thyroid, hand tremor, and weight loss. Symptoms are typically less severe in the elderly and during pregnancy. An uncommon complication is thyroid storm in which an event such as an infection results in worsening symptoms such as confusion and a high temperature and often results in death. The opposite is hypothyroidism, when the thyroid gland does not make enough thyroid hormone. Graves' disease is the cause of about 50% to 80% of the cases of hyperthyroidism in the United States. Other causes include multinodular goit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
