释义 |
DictionarySeehormonecortical hormone
hormone [hor´mōn] a chemical transmitter substance produced by cells of the body and transported by the bloodstream to the cells and organs on which it has a specific regulatory effect. adj., adj hormo´nal. Hormones act as chemical messengers to body organs, stimulating certain life processes and retarding others. Growth, reproduction, control of metabolic processes, sexual attributes, and even mental conditions and personality traits are dependent on hormones. Hormones are produced by various organs and body tissues, but mainly by the endocrine glands, such as the pituitary, thyroid, and gonads (testes and ovaries). Each gland apparently synthesizes several kinds of hormones; the adrenal glands alone produce more than 25 varieties. The total number of hormones is still unknown, but each has its unique function and its own chemical formula. After a hormone is discharged by its parent gland into the capillaries or the lymph, it may travel a circuitous path through the bloodstream to exert influence on cells, tissues, and organs (target organs) far removed from its site of origin. One of the best-known endocrine hormones is insulin, a protein manufactured by the beta cells of the islands of Langerhans in the pancreas that is important in carbohydrate metabolism. Other important hormones are thyroxine, an iodine-carrying amino acid produced by the thyroid gland; cortisone, a member of the steroid family from the adrenal glands; and the sex hormones, estrogen from the ovaries and androgen from the testes. Certain hormone substances can be synthesized in the laboratory for treatment of human disease. Animal hormones can also be used, as endocrine hormones are to some extent interchangeable among species. Extracts from the pancreas of cattle, for example, enabled diabetes sufferers to live normal lives even before the chemistry of insulin was fully understood. Endocrine hormone synthesis and secretion is controlled and regulated by a closed-loop system. Negative feedback loops maintain optimal levels of each hormone in the body. If there are abnormally high levels of a hormone in the blood, feedback to the gland responsible for its production inhibits secretion. If there are abnormally low levels, the gland is stimulated to step up production and secretion. In this way a homeostatic balance is maintained. (See also endocrine glands.)adrenocortical hormone 1. any of the corticosteroids secreted by the adrenal cortex, the major ones being the glucocorticoids and mineralocorticoids, and including some androgens, progesterone, and estrogens.2. corticosteroid.adrenocorticotropic hormone (ACTH) corticotropin.adrenomedullary h's substances secreted by the adrenal medulla, including epinephrine and norepinephrine.androgenic hormone androgen.anterior pituitary hormone any of the protein or polypeptide hormones secreted by the anterior lobe of the pituitary gland" >pituitary gland, including growth hormone, thyrotropin, prolactin, follicle-stimulating hormone, luteinizing hormone, melanocyte-stimulating hormone, and corticotropin.antidiuretic hormone (ADH) vasopressin.corpus luteum hormone progesterone.cortical hormone corticosteroid.corticotropin-releasing hormone (CRH) a neuropeptide secreted by the median eminence of the hypothalamus that binds to specific receptors on the corticotroph cells of the anterior pituitary and stimulates the secretion of corticotropin.ectopic h's those secreted by tumors of nonendocrine tissues but having the same physiologic effects as their normally produced counterparts. It is not known exactly how the synthesis and secretion of endocrine hormones from nonendocrine tissues occurs. Most of these tumors are derived from tissues that have a common embryonic origin with endocrine tissues. When the cells undergo neoplastic transformation, they can revert to a more primitive stage of development and begin to synthesize hormones. Ectopic hormones present serious problems for patients and add to the complexity of caring for those with certain kinds of neoplastic diseases. These hormones do not respond to the feedback mechanisms that regulate normal hormonal production; hence, surgery and destruction of the tumorous tissue by radiation and chemotherapy are the treatments of choice.estrogenic hormone estrogen.follicle-stimulating hormone (FSH) one of the gonadotropins of the anterior pituitary, which stimulates the growth and maturity of graafian follicles in the ovary, and stimulates spermatogenesis in the male.follicle-stimulating hormone and luteinizing hormone–releasing hormone (FSH/LH-RH) luteinizing hormone–releasing hormone.follicle-stimulating hormone–releasing hormone (FSH-RH) luteinizing hormone–releasing hormone.gonadotropic hormone gonadotropin.gonadotropin-releasing hormone (Gn-RH) luteinizing hormone–releasing hormone.growth hormone (GH) any of several related polypeptide hormones secreted by the anterior lobe of the pituitary gland that directly influence protein, carbohydrate, and lipid metabolism and control the rate of skeletal and visceral growth; their secretion is in part controlled by the hypothalamus. It is used pharmaceutically as somatrem and somatropin. Called also somatotrophin, somatotropin, and somatotrophic or somatotropic hormone.growth hormone release–inhibiting hormone somatostatin.growth hormone–releasing hormone (GH-RH) a neuropeptide elaborated by the median eminence of the hypothalamus that binds to specific receptors on the somatotroph cells of the anterior pituitary and stimulates the secretion of growth hormone.interstitial cell–stimulating hormone luteinizing hormone.lactation hormone (lactogenic hormone) prolactin.local hormone a substance with hormone like properties that acts at an anatomically restricted site; most are rapidly degraded. Called also autacoid and autocoid.luteinizing hormone (LH) a gonadotropin of the anterior pituitary gland, acting with follicle-stimulating hormone to cause ovulation of mature follicles and secretion of estrogen by thecal and granulosa cells of the ovary; it is also concerned with corpus luteum formation. In the male, it stimulates development of the interstitial cells of the testes and their secretion of testosterone. Called also interstitial cell–stimulating hormone.luteinizing hormone–releasing hormone (LH-RH) a decapeptide hormone of the hypothalamus, which stimulates the release of follicle-stimulating hormone and luteinizing hormone from the pituitary gland; it can be used in the differential diagnosis of hypothalamic, pituitary, and gonadal dysfunction. Called also follicle-stimulating hormone–releasing hormone, follicle-stimulating hormone and luteinizing hormone–releasing hormone, and gonadotropin-releasing hormone.melanocyte-stimulating hormone (MSH) a substance from the anterior pituitary gland of certain other animals but not humans; it influences the formation or deposition of melanin in the body and pigmentation of the skin.neurohypophyseal h's those stored and released by the neurohypophysis, i.e., oxytocin and vasopressin.parathyroid hormone (PTH) a polypeptide hormone secreted by the parathyroid glands that influences calcium and phosphorus metabolism and bone formation.placental h's hormones secreted by the placenta, including chorionic gonadotropin, and other substances having estrogenic, progestational, or adrenocorticoid activity.progestational hormone 1. progesterone.2. progestational agent.prolactin-inhibiting hormone a hormone released by the hypothalamus that inhibits the secretion of prolactin by the anterior pituitary gland.prolactin-releasing hormone any of various hormones elaborated by the hypothalamus that stimulate the release of prolactin by the anterior pituitary gland. Most such activity is exerted by vasoactive intestinal polypeptide, although in humans hormone" >thyrotropin-releasing hormone can also have this action. sex h's see sex hormones.somatotrophic hormone (somatotropic hormone) growth hormone.somatotropin release–inhibiting hormone somatostatin.somatotropin-releasing hormone (SRH) growth hormone–releasing hormone.steroid h's hormones that are biologically active steroids; they are secreted by the cortex" >adrenal cortex, testis, ovary, and placenta and include the progestational agents, glucocorticoids, mineralocorticoids, androgens, and estrogens. They act by binding to specific receptors to form complexes, which then enhance or inhibit the expression of specific genes.thyroid h's see thyroid hormones.thyroid-stimulating hormone (TSH) thyrotropin.thyrotropin-releasing hormone (TRH) a tripeptide hormone of the hypothalamus, which stimulates release of thyrotropin from the pituitary gland. In humans, it also acts as a prolactinreleasing factor. It is used in the diagnosis of mild hyperthyroidism and Graves disease, and in differentiating between primary, secondary, and tertiary hypothyroidism.cortical hormone A nonspecific term for any steroid hormone produced by the adrenal cortex.hormone (hor'mon?) [Gr. horman, to excite, urge on] 1. A substance originating in an organ, gland, or body part, conveyed through the blood to another body part, and chemically stimulating that part to increase or decrease functional activity or to increase or decrease secretion of another hormone.2. The secretion of the ductless glands, e.g., insulin from the pancreas. See: endocrine glandhormonal (hor-mon'al), adjectiveadrenocortical hormone Abbreviation: ACH A hormone (such as aldosterone or cortisol) secreted by the cortex of the adrenal gland. Synonym: cortical hormone See: adrenal glandadrenocorticotropic hormone Abbreviation: ACTH A hormone that is secreted by the anterior lobe of the pituitary gland and controls the development and functioning of the adrenal cortex, including its secretion of glucocorticoids and androgens. Synonym: corticotropinadrenomedullary hormoneAny of several hormones (such as epinephrine and norepinephrine) produced by the adrenal medulla.androgenic hormoneAndrogen.anterior pituitary hormoneAny of several hormones secreted by the anterior lobe of the pituitary, including corticotropin, follicle-stimulating hormone, gonadotropin, growth hormone, luteinizing hormone, melanocyte-stimulating hormone, prolactin, and thyrotropin.antidiuretic hormone Abbreviation: ADH A peptide hormone that plays a crucial role in limiting the amount of water excreted by the kidneys. Deficiency of ADH causes central diabetes insipidus, excess causes water retention and hyponatremia. Synonym: vasopressinADH is produced by the hypothalamus and stored in the posterior pituitary gland; it is secreted when the osmolarity of plasma rises. Secretion of ADH increases the concentration of the urine by preventing water losses from the renal tubules. ADH also causes constriction of arterioles (raising blood pressure) and increases levels of clotting factor VIII. ADH can be administered to patients in cardiac arrest as an alternative to epinephrine. atrial natriuretic hormoneAtrial natriuretic factor.bioidentical natural hormoneBioidentical synthetic hormone.bioidentical synthetic hormone Abbreviation: BSH A compound extracted from plants or formulated in the laboratory and used to replace or increase concentrations of hormones found in the body. The most commonly manufactured and marketed BSHs are the sex steroid hormones (estrogen, progesterone, and testosterone). Synonym: bioidentical natural hormonecalcitonin hormoneCalcitonin.corpus luteum hormoneProgesterone.cortical hormoneAdrenocortical hormone.corticotropin-releasing hormone Abbreviation: CRH A hormone that is released from the hypothalamus and acts on the anterior pituitary to increase secretion of adrenal corticotropin hormone. In response to stress, CRH causes hyperglycemia, increased oxygen consumption, increased cardiac output, and decreased sexual activity; suppresses release of growth hormone; diminishes gastrointestinal function; stimulates respiration; and causes behavioral changes. Synonym: corticotropin-releasing factorcounterregulatory hormoneAny of the hormones that oppose the effects of insulin. They include glucagon, epinephrine, norepinephrine, cortisol, and growth hormone. digestive hormoneAny of a group of hormones produced by the stomach or small intestinal mucosa and stimulating various tissues to release enzymes, produce fluids, or affect gastrointestinal motility. They include gastrin, motilin, secretin, cholecystokinin, and vasoactive intestinal peptide. estrogenic hormoneEstrogen.follicle-stimulating hormone Abbreviation: FSH A hormone that is secreted by the anterior lobe of the pituitary and stimulates maturation of the ovarian follicles in women. In men, the hormone is important in maintaining spermatogenesis. follicle-stimulating hormone releasing hormone Abbreviation: FSH-RH A hormone from the hypothalamus that regulates release of follicle-stimulating hormone.gastric hormoneGastrin.gonadotropic hormone, gonadotrophic hormoneGonadotropin.gonadotropin-releasing hormone Abbreviation: Gn-RH The hormone produced in the hypothalamus that causes the pituitary to release luteinizing hormone and follicle-stimulating hormone. This hormone is used in treating endometriosis. Synonym: luteinizing hormone-releasing hormonegrowth hormone Abbreviation: GH A hormone secreted by the anterior pituitary and regulating the cell division and protein synthesis necessary for normal growth. It is a protein made from a single chain of amino acids; molecular weight 22 kDa. Synonym: somatotropingrowth hormone-releasing hormone Abbreviation: GH-RH A hormone from the hypothalamus that stimulates the release of growth hormone. Synonym: somatotropin-releasing hormonehuman growth hormone Abbreviation: HGH See: growth hormonehuman placental lactogen hormone See: human placental lactogenimmunoregulatory hormoneA hormone that influences components of the immune system, including the number and activity of the white blood cells. Such hormones are secreted by almost all of the glands in the body, particularly the hypothalamus and adrenal glands. inhibitory hormoneAny of a group of substances limiting the release of hormones from the pituitary. Somatostatin, which inhibits the release of growth hormone, is included in this group. interstitial cell-stimulating hormone Abbreviation: ICSH An obsolete term for luteinizing hormone. intestinal hormoneAny of several hormones produced by the mucosa of the intestine. They include cholecystokinin, motilin, secretin, and vasoactive inhibitory peptide. lipolytic hormoneAny hormone (such as epinephrine, glucagon, and cortisol) that promotes release of free fatty acids from fat tissue. luteal hormoneProgesterone.luteinizing hormone Abbreviation: LH A hormone produced by the anterior lobe of the pituitary, in females stimulating the development of the corpus luteum and helping in the secretion of progesterone, and in males stimulating the development of interstitial cells of the testes to produce testosterone. Synonym: luteotropic hormoneluteinizing hormone-releasing hormone Abbreviation: LH-RH Gonadotropin-releasing hormone.luteotropic hormone Abbreviation: LTH Luteinizing hormone.melanocyte-stimulating hormone Abbreviation: MSH A hormone of the anterior pituitary gland that causes pigmentation of the skin in humans. Synonym: intermedinovarian hormoneA hormone produced by the ovary. See: estradiol; estriol; estrogen; estrone; progesteronepancreatic hormoneA hormone produced by the islets of Langerhans of the pancreas. See: glucagon; insulinparathyroid hormone Abbreviation: PTH A hormone secreted by the parathyroid glands that regulates blood levels of calcium and phosphorus. A deficiency results in hypoparathyroidism and hypocalcemia; in excess, it causes hyperparathyroidism and hypercalcemia. Synonym: parathormoneplacental hormoneAny of the hormones secreted by the placenta, including estrogen, progesterone, and human chorionic gonadotropin. posterior pituitary hormoneAny of the hormones secreted by the posterior lobe of the pituitary (such as vasopressin and oxytocin). See: antidiuretic hormoneprogestational hormoneProgesterone.releasing hormone Abbreviation: RH Any of a group of substances secreted by the hypothalamus that control or inhibit the release of various hormones. They include thyrotropin-releasing hormone, gonadotropin-releasing hormone, dopamine, growth hormone-releasing hormone, corticotropin-releasing hormone, and somatostatin. Dopamine and somatostatin act to inhibit release of the hormones they act upon. sex hormoneAn androgen or an estrogen.somatotropic hormone Abbreviation: STH Somatotropin.somatotropin-releasing hormoneGrowth hormone-releasing hormone.steroid hormoneOne of the sex hormones and hormones of the adrenal cortex.synthetic human growth hormoneA growth hormone made with recombinant DNA techniques. testicular hormoneA hormone produced by the interstitial tissue of the testis (such as testosterone and inhibin).thymic hormoneAny of the hormones produced by the thymus that may help attract lymphoid stem cells to the thymus and stimulate their development into mature T lymphocytes. They include thymulin, thymopoietin, and thymosin. thyroid hormoneEither of two hormones, thyroxine (T4) or triiodothyronine (T3, secreted by the follicles of the thyroid gland. They act on receptors in tissues throughout the body to increase the production of cellular proteins, the metabolic rate, and the activities of the sympathetic nervous system. Deficiency of thyroid hormone produces clinical hypothyroidism; excess causes hyperthyroidism. thyroid-stimulating hormone Abbreviation: TSH Thyrotropin.thyrotropic hormoneThyrotropin.thyrotropin-releasing hormone Abbreviation: TRH A hormone secreted by the hypothalamus that stimulates the anterior pituitary to release thyrotropin. It was formerly called thyroid-stimulating hormone-releasing factor. tropic hormoneA hormone secreted by one gland (e.g. the pituitary gland) that stimulates another gland to secrete its hormone or hormones. |