A peptide's response may depend on which pathway an assay measures.
More than an on/off switch
G-protein-coupled receptors can be assessed through several downstream responses. Work on the GLP-1 receptor found that features of its extracellular surface influenced biased agonism, where ligands favour different signalling patterns. This is a mechanistic finding in the studied models.
Compare like with like
A single reported potency value does not describe every pathway or time point. When comparing ligands, check whether the papers used the same cells, receptor expression, reference agonist and readout. A difference in assay architecture can look like a difference in the material itself.
Name the measured pathway and experimental model before summarising a peptide as simply “stronger” or “weaker.”
Sources
Read the original studies or guidance for methods, populations and limitations.
This article is general research information. It is not a Certificate of Analysis for an MC10 product or medical advice. MC10 materials are presented for in-vitro research only.
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