Antagonist
Antagonist
Antagonist (/ænˈtæɡənɪst/) is a term used in the field of medicine and pharmacology to refer to a substance that interferes with or inhibits the physiological action of another, particularly the blocking of a receptor.
Etymology
The term 'antagonist' is derived from the Greek word 'antagonistes', which means 'opponent' or 'competitor'. In the medical context, it was first used in the mid-18th century to describe a substance that counteracts the effects of another substance in the body.
Types of Antagonists
There are several types of antagonists, including:
- Competitive antagonist: A competitive antagonist competes with the agonist for the same receptor site. The presence of a competitive antagonist reduces the effective concentration of the agonist.
- Non-competitive antagonist: A non-competitive antagonist binds to a site different from the agonist, altering the receptor's activity and reducing the effect of the agonist.
- Uncompetitive antagonist: An uncompetitive antagonist binds to the receptor only after the agonist has bound, locking the receptor in an inactive state.
- Inverse agonist: An inverse agonist produces an effect opposite to that of the agonist, even when the agonist is not present.
Related Terms
- Agonist: An agonist is a substance that initiates a physiological response when combined with a receptor.
- Receptor: A receptor is a protein molecule that receives chemical signals from outside a cell.
- Pharmacodynamics: Pharmacodynamics is the study of how a drug affects an organism.
- Pharmacokinetics: Pharmacokinetics is the study of how an organism affects a drug.
External links
- Medical encyclopedia article on Antagonist
- Wikipedia's article - Antagonist
This WikiMD dictionary article is a stub. You can help make it a full article.
Languages: - East Asian
中文,
日本,
한국어,
South Asian
हिन्दी,
Urdu,
বাংলা,
తెలుగు,
தமிழ்,
ಕನ್ನಡ,
Southeast Asian
Indonesian,
Vietnamese,
Thai,
မြန်မာဘာသာ,
European
español,
Deutsch,
français,
русский,
português do Brasil,
Italian,
polski