Glossary of Pharmacology 

Antagonist

A ligand that binds to the receptor but does not elicit any biological response and prevents the biological response elicited by an agonist. Antagonists do not trigger a conformational change in the receptor that initiates signalling cascades or translates into a biological effect. 

Example:

Atenolol is an antagonist that binds to β₁-adrenergic receptor in the heart and elicits no biological response, but it blocks the tachycardic action of catecholamines on the heart leading to a reduction in heart rate.  

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