| herz hormone | A substance present in extracts of cardiac tissue that augments cardiac contraction; possibly adenosine, a catecholamine, or some non-specific stimulant present generally in tissues. Synonym: cardiac hormone, heart hormone. (05 Mar 2000) |
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| hormone | <endocrinology> A naturally occuring substance secreted by specialised cells that affects the metabolism or behaviour of other cells possessing functional receptors for the hormone. Hormones may be hydrophilic, like insulin, in which case the receptors are on the cell surface or lipophilic, like the steroids, where the receptor can be intracellular. Some cancers may be stimulated and others inhibited by hormones (for example breast and prostate cancer). Some hormones can be synthesised and used as replacement in glandular deficiencies or as treatment for some cancers. Hormones may be injected, others taken by mouth. (29 Sep 1997) |
| hormone, aldosterone | Hormone produced by the outer portion (cortex) of the adrenal gland that regulates the balance of water and electrolytes (ions such as potassium and sodium) in the body. Aldosterone encourages the kidney to excrete potassium into the urine and to retain sodium, thereby retaining water. Aldosterone is classified as a mineralocorticoid hormone. (12 Dec 1998) |
| hormone, androgenic | Any hormone that promotes the development and maintenance of male sex characteristics. Testosterone is an androgen. (12 Dec 1998) |
| hormone antagonists | Chemical substances which inhibit the function of the endocrine glands, the biosynthesis of their secreted hormones, or the action of hormones upon their specific sites. (12 Dec 1998) |
| hormone, cortisol | The primary stress hormone. Cortisol is the major natural glucocorticoid in humans. (12 Dec 1998) |
| hormone, glucocorticoid | A hormone that predominantly affects the metabolism of carbohydrates and,to a lesser extent, fats and proteins (and has other effects). Glucocorticoids are made in the outside portion (the cortex) of the adrenal gland and chemically classed as steroids. Cortisol is the major natural glucocorticoid. The term glucocorticoid also applies to equivalent hormones synthesised in the laboratory. (12 Dec 1998) |
| hormone, human chorionic gonadotropin | A human hormone made by chorionic cells (in the foetal part of the placenta), hcg is directed at the gonads and stimulates them. Hcg becomes detectable (by immunologic means) within days of the time of fertilization. It therefore forms the foundation of most common pregnancy tests. The level of hcg in maternal serum enters as one component in the double and the triple screens used during pregnancy to assign risks of down syndrome and other foetal disorders. (12 Dec 1998) |
| hormone, mineralocorticoid | A group of hormones, the most important being aldosterone, that regulate the balance of water and electrolytes (ions such as sodium and potassium) in the body. The mineralocorticoid hormones act specifically on the tubules of the kidney. (12 Dec 1998) |
| hormone, parathormone | Hormone made by the parathyroid gland (behind the thyroid gland in the neck). Parathormone (pronounced para-thor-mone) is critical to calcium and phosphorus balance. Deficiency of parathormone results in abnormally low calcium in the blood (hypocalcaemia). Also call parathyrin. (12 Dec 1998) |
| hormone, parathyrin | See Hormone, parathormone. (12 Dec 1998) |
| hormone, parathyroid | See Hormone, parathormone. (12 Dec 1998) |
| hormone, progesterone | A female hormone, progesterone is the principal progestational hormone. Progestational hormones prepare the uterus (the womb) to receive and sustain the fertilised egg. (12 Dec 1998) |
| hormone receptor assay | A diagnostic test to determine whether a breast cancer's growth is influenced by hormones or if it can be treated with hormones. (09 Oct 1997) |
| hormone replacement therapy | In females, treatment with sex hormones for a number for reasons, including menopause, partial or full hysterectomy, or amenorrhoea.In women, treatment with sex hormones is indicated for a number of reasons, including menopause, partial or full hysterectomy, or amenorrhoea. After menopause, conjugated oestrogens, estradiol, or estrone sulfate are given to reduce pain during intercourse, limit blood vessel effects, and prevent loss of bone mass. After radical hysterectomy, conjugated oestrogens are given for similar reasons. After menopause or partial hysterectomy, progestin is administered at the same time to offset an increased risk of endometrial cancer. In some amenorrhoeas, oestrogen is given to restore menses; if the therapy is unsuccessful, this may indicate the presence of pathology, for instance, pituitary tumour. Benefits for postmenopausal women include a lowered risk of heart attack (oestrogen lowers LDL and raises HDL levels), and prevention of osteoporosis, since the rate of bone loss is directly linked to a drop in oestrogen levels (see perimenopause). Medical opinion about the hazard posed by such therapy remains divided. Some studies have indicated increased incidence of breast cancer; however, a comprehensive 1992 review of the literature contradicted this finding. (05 Mar 2000) |