15 Facts About Receptor antagonists

Receptor antagonists antagonist is a type of receptor ligand or drug that blocks or dampens a biological response by binding to and blocking a receptor rather than activating it like an agonist.

In pharmacology, antagonists have affinity but no efficacy for their cognate receptors, and binding will disrupt the interaction and inhibit the function of an agonist or inverse agonist at receptors.

The majority of drug antagonists achieve their potency by competing with endogenous ligands or substrates at structurally defined binding sites on receptors.

The affinity constant of Receptor antagonists exhibiting two or more effects, such as in competitive neuromuscular-blocking agents that block ion channels as well as antagonising agonist binding, cannot be analyzed using Schild regression.

Affinity for competitive agonists and Receptor antagonists is related by the Cheng-Prusoff factor used to calculate the Ki from the shift in IC50 that occurs during competitive inhibition.

Competitive antagonists bind to receptors at the same binding site as the endogenous ligand or agonist, but without activating the receptor.

Competitive Receptor antagonists are used to prevent the activity of drugs, and to reverse the effects of drugs that have already been consumed.

Competitive antagonists are sub-classified as reversible or irreversible competitive antagonists, depending on how they interact with their receptor protein targets.

Unlike competitive Receptor antagonists, which affect the amount of agonist necessary to achieve a maximal response but do not affect the magnitude of that maximal response, non-competitive Receptor antagonists reduce the magnitude of the maximum response that can be attained by any amount of agonist.

Uncompetitive antagonists differ from non-competitive antagonists in that they require receptor activation by an agonist before they can bind to a separate allosteric binding site.

Silent antagonists are competitive receptor antagonists that have zero intrinsic activity for activating a receptor.

Many drugs previously classified as antagonists are now beginning to be reclassified as inverse agonists because of the discovery of constitutive active receptors.

Many antagonists are reversible antagonists that, like most agonists, will bind and unbind a receptor at rates determined by receptor-ligand kinetics.

Irreversible antagonists covalently bind to the receptor target and, in general, cannot be removed; inactivating the receptor for the duration of the antagonist effects is determined by the rate of receptor turnover, the rate of synthesis of new receptors.

Irreversible competitive antagonists involve competition between the agonist and antagonist of the receptor, but the rate of covalent bonding differs and depends on affinity and reactivity of the antagonist.