agonist
An agonist is a chemical that activates a Receptor (biochemistry), receptor to produce a biological response. Receptors are Cell (biology), cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an R ...
antagonist
An antagonist is a character in a story who is presented as the main enemy or rival of the protagonist and is often depicted as a villain.μ1-opioid receptor. It produces
analgesia
Pain management is an aspect of medicine and health care involving relief of pain (pain relief, analgesia, pain control) in various dimensions, from acute and simple to chronic and challenging. Most physicians and other health professionals ...
in animals that differs from that of conventional
μ-opioid receptor
The μ-opioid receptors (MOR) are a class of opioid receptors with a high affinity for enkephalins and beta-endorphin, but a low affinity for dynorphins. They are also referred to as μ(''mu'')-opioid peptide (MOP) receptors. The prototypical ...
agonists but that can still be blocked by μ-opioid receptor antagonists. TRIMU-5 can also block the analgesic effects of μ-opioid receptor agonists like
morphine
Morphine, formerly also called morphia, is an opiate that is found naturally in opium, a dark brown resin produced by drying the latex of opium poppies (''Papaver somniferum''). It is mainly used as an analgesic (pain medication). There are ...
. In addition to analgesia, TRIMU-5 inhibits gastrointestinal transit, a known effect of μ2-opioid receptor activation.