Fluorophen, or fluorofen, is a fluorinated analogue of

phenazocine Phenazocine (brand names Prinadol, Narphen) is an opioid analgesic drug, which is related to pentazocine and has a similar profile of effects. Effects of phenazocine include analgesia and euphoria, also may include dysphoria and hallucinations at ...

, an

opioid Opioids are a class of Drug, drugs that derive from, or mimic, natural substances found in the Papaver somniferum, opium poppy plant. Opioids work on opioid receptors in the brain and other organs to produce a variety of morphine-like effects, ...

drug A drug is any chemical substance other than a nutrient or an essential dietary ingredient, which, when administered to a living organism, produces a biological effect. Consumption of drugs can be via insufflation (medicine), inhalation, drug i ...

of the

benzomorphan Benzomorphan is a chemical compound that is the base for a series of drugs which variably act on the sigma receptors and κ-opioid receptors, including the following compounds: * 5,9-DEHB * 8-CAC * Alazocine * Anazocine * Bremazocine * Buti ...

group, which was developed as a

radioligand A radioligand is a microscopic particle which consists of a Radiopharmaceutical, therapeutic radioactive isotope and the cell-targeting compound - the ligand. The ligand is the target binding site, it may be on the surface of the targeted cancer c ...

for the purpose of labeling

opioid receptor Opioid receptors are a group of inhibitory G protein-coupled receptors with opioids as ligands. The endogenous opioids are dynorphins, enkephalins, endorphins, endomorphins and nociceptin. The opioid receptors are ~40% identical to somatostati ...

s during

PET scans Positron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in metabolic processes, and in other physiological activities including blood flow, re ...

(with ¹⁸F). Unlike most other benzomorphan derivatives, fluorophen acts as a

full agonist An agonist is a chemical that activates a receptor to produce a biological response. Receptors are cellular proteins whose activation causes the cell to modify what it is currently doing. In contrast, an antagonist blocks the action of the agoni ...

of the opioid receptors with preferential

affinity Affinity may refer to: Commerce, finance and law * Affinity (law), kinship by marriage * Affinity analysis, a market research and business management technique * Affinity Credit Union, a Saskatchewan-based credit union * Affinity Equity Pa ...

for the

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 ...

(approximately 6x that of morphine), similar but slightly lower affinity for the

δ-opioid receptor The δ-opioid receptor, also known as delta opioid receptor or simply delta receptor, abbreviated DOR or DOP, is an inhibitory 7-transmembrane G-protein coupled receptor coupled to the G protein Gi alpha subunit, Gi/G0 and has enkephalins as it ...

(equipotent to small>D-Ala², D-Leu⁵nkephalin), and very low affinity for the

κ-opioid receptor The κ-opioid receptor or kappa opioid receptor, abbreviated KOR or KOP for its ligand ketazocine, is a G protein-coupled receptor that in humans is encoded by the ''OPRK1'' gene. The KOR is coupled to the G protein Gi/G0 and is one of four re ...

References

Benzomorphans Opioids 4-Fluorophenyl compounds Hydroxyarenes {{Nervous-system-drug-stub