part of negative regulation of activin receptor signaling pathway activin receptor antagonist activity bf GO:0038102 This term refers to inhibition of a member of the activin receptor family; activin receptors bind to multiple ligands including activin and nodal. Interacting with an activin receptor complex to reduce the action of another ligand, the agonist. A receptor antagonist does not initiate signaling upon binding to a receptor, but instead blocks an agonist from binding to the receptor. 2012-02-17T11:28:59Z molecular_function receptor antagonist activity