Red-Emitting Dibenzodiazepinone Derivatives as Fluorescent Dualsteric Probes for the Muscarinic Acetylcholine M2 Receptor.
J Med Chem
; 63(8): 4133-4154, 2020 04 23.
Article
in En
| MEDLINE
| ID: mdl-32233403
ABSTRACT
Fluorescently labeled dibenzodiazepinone-type muscarinic acetylcholine receptor (MR) antagonists, including dimeric ligands, were prepared using red-emitting cyanine dyes. Probes containing a fluorophore with negative charge showed high M2R affinities (pKi (radioligand competition binding) 9.10-9.59). Binding studies at M1 and M3-M5 receptors indicated a M2R preference. Flow cytometric and high-content imaging saturation and competition binding (M1R, M2R, and M4R) confirmed occupation of the orthosteric site. Confocal microscopy revealed that fluorescence was located mainly at the cell membrane (CHO-hM2R cells). Results from dissociation and saturation binding experiments (M2R) in the presence of allosteric M2R modulators (dissociation W84, LY2119620, and alcuronium; saturation binding W84) were consistent with a competitive mode of action between the fluorescent probes and the allosteric ligands. Taken together, these lines of evidence indicate that these ligands are useful fluorescent molecular tools to label the M2R in imaging and binding studies and suggest that they have a dualsteric mode of action.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Phthalimides
/
Muscarinic Antagonists
/
Receptor, Muscarinic M2
/
Fluorescent Dyes
/
Quaternary Ammonium Compounds
Limits:
Animals
Language:
En
Journal:
J Med Chem
Journal subject:
QUIMICA
Year:
2020
Document type:
Article
Affiliation country:
Germany