If you experience chronic constipation, or if eating prunes and drinking prune juice doesnât solve your problems, contact your doctor for professional advice. Also, make sure to talk to your doctor if you begin to experience: 1  rectal or abdominal pain.  blood in stool.
agonist agÂ·oÂ·nist (Äg'É-nÄ­st) n. A contracting muscle that is resisted or counteracted by an antagonistic muscle. A substance that can combine with a cell receptor to produce a reaction typical for that substance.
Efficacy spectrum of receptor ligands. An agonist is a chemical that binds to a receptor and activates the receptor to produce a biological response. Whereas an agonist causes an action, an antagonist blocks the action of the agonist and an inverse agonist causes an action opposite to that of the agonist.ypes of agonists [edit]. Receptors can be activated by either endogenous (such as hormones and neurotransmitters) or exogenous (such as drugs) agonists, resulting in a biological response.