1. a substance that initiates a physiological response when combined with a receptor on a cell or organism
Usage: pharmacology and biochemistry term
2. a muscle that contracts to produce a movement, often opposed by an antagonist muscle
Usage: anatomy and physiology term

Examples

• Dopamine acts as an agonist at dopamine receptors in the brain.
• The drug works by binding to the receptor as an agonist, triggering the desired cellular response.
• When you flex your biceps, the biceps muscle acts as the agonist while the triceps acts as the antagonist.
• Partial agonists produce a weaker response than full agonists at the same receptor.
• The medication is designed to be a selective agonist for a specific receptor subtype.