Medical dictionary. 2011.
Competitive antagonist — A competitive antagonist is a receptor antagonist that binds to a receptor but does not activate the receptor. The antagonist will compete with available agonist for receptor binding sites on the same receptor. Sufficient antagonist will displace … Wikipedia
Antagonist — In biochemistry, an antagonist acts against and blocks an action. For example, insulin lowers the level of glucose (sugar) in the blood, whereas another hormone called glucagon raises it; therefore, insulin and glucagon are antagonists. An… … Medical dictionary
competitive inhibition — inhibition of enzyme activity in which the inhibitor (substrate analogue) reversibly combines with catalytic sites, thus competing with the substrate for binding on the enzyme. The inhibition is reversible since it can be overcome by increasing… … Medical dictionary
Receptor antagonist — This article is about the biochemistry term. For other uses, see Antagonist (disambiguation). Antagonists will block the binding of an agonist at a receptor molecule, inhibiting the signal produced by a receptor agonist coupling. A receptor… … Wikipedia
5-HT3 antagonist — 5 HT3 receptor antagonists Drug class Skeletal formula of ondansetron, the prototypical 5 HT3 antagonist ATC code A04AA … Wikipedia
H2 antagonist — The H2 receptor antagonists (H2RA, often shortened to H2 antagonist) are a class of drugs used to block the action of histamine on parietal cells in the stomach, decreasing the production of acid by these cells. H2 antagonist are used in the… … Wikipedia
NMDA receptor antagonist — Ketamine, one of the most common NMDA receptor antagonists. NMDA receptor antagonists are a class of anesthetics that work to antagonize, or inhibit the action of, the N methyl d aspartate receptor (NMDAR). They are used as anesthesia for animals … Wikipedia
Muscarinic antagonist — In neurochemistry, a muscarinic receptor antagonist is an agent that reduces the activity of the muscarinic acetylcholine receptor. Acetylcholine (often abbreviated ACh) is a neurotransmitter, whose receptor is a protein found in synapses and… … Wikipedia
Histamine antagonist — A histamine antagonist, commonly referred to as antihistamine, is a pharmaceutical drug that inhibits action of histamine by blocking it from attaching to histamine receptors. Contents 1 Clinical effects 2 Clinical: H1 and H2 receptor antagonists … Wikipedia
Opioid antagonist — An opioid antagonist is a receptor antagonist that acts on opioid receptors. Naloxone and naltrexone are commonly used opioid antagonist drugs which are competitive antagonists that bind to the opioid receptors with higher affinity than agonists… … Wikipedia
