antiandrogen

(redirected from Androgen antagonist)
Also found in: Dictionary.

androgen

 [an´dro-jen]
any steroid hormone that promotes male secondary sex characters. The two main androgens are androsterone and testosterone. Called also androgenic hormone. adj., adj androgen´ic. 

The androgenic hormones are internal endocrine secretions circulating in the bloodstream and manufactured mainly by the testes under stimulation from the pituitary gland. To a lesser extent, androgens are produced by the adrenal glands in both sexes, as well as by the ovaries in women. Thus women normally have a small percentage of male hormones, in the same way that men's bodies contain some female sex hormones, the estrogens. Male secondary sex characters include growth of the beard and deepening of the voice at puberty. Androgens also stimulate the growth of muscle and bones throughout the body and thus account in part for the greater strength and size of men as compared to women.
androgen insensitivity syndrome complete androgen resistance.

an·ti·an·dro·gen

(an'tē-an'drō-jen),
Any substance capable of preventing full expression of the biologic effects of androgenic hormones on responsive tissues, either by producing antagonistic effects on the target tissue, as estrogens do, or by merely inhibiting androgenic effects, such as by competing for binding sites at the cell surface.

antiandrogen

(ăn′tē-ăn′drə-jən, ăn′tī-)
n.
A substance that inhibits the biological effects of androgenic hormones.

antiandrogen

Endocrinology A hormone or other agent–eg, megestrol acetate, spironolactone, flutamide, nilutamide, and cimetidine, which interferes with androgen function by competitively inhibiting androgen binding to cognate receptors at the target organ and is either biologically inert or functionally very weak; these compounds are used to manage androgen-dependent CAs–♂ breast and prostate, hirsutism, acne

Antiandrogen

A substance that blocks the action of androgens, the hormones responsible for male characteristics. Used to treat prostate cancers that require male hormones for growth.
Mentioned in: Prostate Cancer
References in periodicals archive ?
Low-level exposure to endocrine-disrupting compounds can induce functional, developmental, behavioral, and transgenerational disturbances, as shown after low-level exposure to the fungicide vin-clozolin, which acts as an androgen antagonist in rats and mice (Anway et al.
These studies led to the identification of several estrogen receptor (ER) agonists as being androgen antagonists. However, although an earlier study demonstrated that 2-tert-butylanthraquinone and benzoanthrone may act as weak agonists to the human androgen receptor (hAR) at high concentrations (Araki et al.
Four laboratories assessed the detection of this androgen antagonist using doses of 3, 10, 30, and 100 mg PRO/kg bw/day coadministered with 0.4 mg TP/kg bw/day.
Four laboratories assessed the detection of this weak androgen antagonist using doses of 3, 10, 30, and 100 mg LIN/kg bw/day coadministered with 0.4 mg TP/kg bw/day.
CONCLUSIONS: The results show that the OECD Hershberger bioassay protocol is reproducible and transferable across laboratories with androgen agonists, weak androgen antagonists, and a 5[alpha]-reductase inhibitor.
Louis, MO, USA; 99.9% pure), and the reference androgen antagonist (FLU) (CASRN 13311-84-7) was from Salutas Pharma (Barleben, Germany; 99.9% pure).
Based on this phase 1 validation study, the protocols have been refined, and the next phase of the OECD validation program will test the protocol with selected doses of weak androgen agonists, androgen antagonists, a 5[alpha]-reductase inhibitor, and chemicals having no androgenic activity.
Then, the assay was adapted for androgen antagonists such as flutamide (FLU) (Peets et al.
(18) Low androgen levels, such as in those who are androgen deficient or using androgen antagonists, can result in reduced quality and quantity of meibomian lipids which is seen clinically as increased tear film instability and reduced tear break-up time (TBUT).
All test systems showed that bicalutamide and hydroxyflutamide act as potent androgen antagonists (Ma et al.
This modified system was successfully used by several investigators for assaying androgen antagonists (Peers et al.
For the androgen antagonists (VCZ and p,p'-DDE), 0.2 mg/kg/day of TP was coadministered each day by subcutaneous injection in the dorsal region after the oral administration of each chemical.