antiestrogen

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estrogen

 [es´tro-jen]
a generic term for any of the estrus-producing compounds (female sex hormones), including estradiol, estriol, and estrone. Called also estrogenic hormone. In humans, the estrogens are formed in the ovary, adrenal cortex, testis, and fetoplacental unit, and are responsible for female secondary sex characteristic development, and during the menstrual cycle, act on the female genitalia to produce an environment suitable for fertilization, implantation, and nutrition of the early embryo. Uses for estrogens include oral contraceptives, hormone replacement therapy, advanced prostate or postmenopausal breast carcinoma treatment, and osteoporosis prophylaxis.
conjugated e's a mixture of the sodium salts of the sulfate esters of estrone and equilin; therapeutic uses are similar to those of other estrogens; administered orally, intravenously, intramuscularly, or intravaginally.
esterified e's a mixture of esters of estrogenic substances, principally estrone, having therapeutic uses similar to those of other estrogens.

an·ti·es·tro·gen

(an'tē-es'trō-jen),
Any substance capable of preventing full expression of the biologic effects of estrogenic hormones on responsive tissues, either by producing antagonistic effects on the target tissue, as androgens and progestogens do, or by competing with estrogens at estrogen receptors at the cellular level (for example, tamoxifen).
Synonym(s): estrogen antagonist

antiestrogen

/an·ti·es·tro·gen/ (-es´tro-jen) a substance capable of inhibiting the biological effects of estrogens.antiestrogen´ic

antiestrogen

[-es′trəjən]
a hormone-based product used predominantly in cancer chemotherapy. The group of antiestrogen drugs includes tamoxifen. They are used mainly in treating estrogen-dependent tumors, such as breast cancer.

an·ti·es·tro·gen

(an'tē-es'trō-jĕn)
Any substance capable of preventing full expression of the biologic effects of estrogenic hormones on responsive tissues.
Synonym(s): antioestrogen.

antiestrogen

1. blocking the action of estrogens.
2. an agent that so acts.
References in periodicals archive ?
It is thought to have an estrogen agonist effect on bone and an estrogen antagonist effect on breast tissue.
It is thought to be an estrogen antagonist on the uterus and mammary tissues and an estrogen agonist with respect to bone and serum lipids and breast tissue.
Raloxifene had initially been thought to be a possible estrogen antagonist in the CNS because of its propensity to induce hot flashes.
A similar induction is achieved with micromolar levels of cadmium, and both responses are blocked by estrogen antagonists (Stolen et al.
57-63-6), and the reference estrogen antagonist was the pure antagonist ZM 189,154 (ZM; CAS no.
Most known estrogen antagonists such as tamoxifen will also express low levels of an agonist response and would complicate data interpretation by responding as a positive in both agonist and antagonist sections of the assay (15).
In addition, estrogen antagonists can be identified by blocking or reducing the uterine weight increase of a reference agonist when both are simultaneously administered.
Also, application of estrogen antagonists such as tamoxifen, and aromatase inhibitors such as fadrazole have successfully sex-reversed genetic females to phenotypic males.
Pipeline candidates fall under major therapeutic classes such as estrogen antagonists, female gamete inhibitor, insulin secretion inhibitor, HMG CoA inhibitor, Gastric and pancreatic lipase inhibitor and fats break down inhibitor.
2004) noted, the experimental data show that TCDD and other estrogen antagonists delay vaginal opening (VO) and disrupt cyclicity in rodents treated prenatally (Gray et al.
However, we cannot rule out that newly identified receptors such as SXR and PXR [reviewed by Blumberg and Evans (62)], which are activated by a variety of different compounds, including estrogen antagonists and agonists, could be involved in the activation/repression of some of the estrogen-sensitive genes we have identified.