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.
antagonist: a compound that blocks or inhibits the action of a neurotransmitter. direct-acting antagonist (aka receptor blocker): binds to the same receptor population as an agonist but fails to activate the target receptors.competitive antagonist: competes with an agonist for the same receptor population.ntagonist: a compound that blocks or inhibits the action of a neurotransmitter. direct-acting antagonist (aka receptor blocker): binds to the same receptor population as an agonist but fails to activate the target receptors.