The word agonist comes up constantly in peptide research. In simple terms, an agonist is a molecule that activates a receptor. Here’s what that means and why it matters.
- Receptor: a protein on (or in) a cell that receives a signal.
- Agonist: a molecule that binds a receptor and switches it on.
- Why it matters: many studied peptides are described as agonists of a specific receptor.
How an agonist works
Think of a receptor as a lock and the agonist as a key that turns it. When an agonist binds, it triggers the receptor’s normal response inside the cell. A molecule that binds but blocks the response instead is called an antagonist — see Agonist vs Antagonist.
Agonists in peptide research
Many research peptides are classified by the receptor they activate. A few examples from the research literature:
- Incretin receptor agonists act on GLP-1, GIP and glucagon receptors.
- Growth-hormone secretagogues act on the GHRH or ghrelin receptors.
New to the terminology? See the research glossary.
Browse research-grade peptides
Lab-tested, with third-party purity verification.