title: Selective signaling via unique M1 muscarinic agonists.
abstract: Rigid analogs of acetylcholine (ACh) were designed for selective actions at muscarinic receptor (mAChR) subtypes and distinct second messenger systems. AF102B, AF150, and AF151 are such rigid analogs of ACh. AF102B, AF150 and AF151 are centrally active M1 agonists. AF102B has a unique agonistic profile showing, inter alia: only part of the M1 electrophysiology of ACh and unusual binding parameters to mAChRs. AF150 and AF151 are more efficacious agonists than AF102B for M1 AChRS in rat cortex and in CHO cells stably transfected with the m1 AChR subtype. Notably, the selectivity of the new m1 agonists is reflected also by activation of select second messenger systems via distinct G-proteins. These compounds reflect a new pharmacological concept, tentatively defined as ligand-selective signaling. Thus, agonist/m1AChR complexes may activate different combinations of signaling pathways, depending on the ligand used. Rigid agonists may activate a limited repertoire of signaling systems. In various animal models for Alzheimer's disease (AD) the agonists AF102B, AF150 and AF151, exhibited positive effects on mnemomic processes and a wide safety margin. Such agonists, and especially AF102B, can be considered as a rational treatment strategy for AD.
authors.affiliation: Israel Institute for Biological Research, Ness-Ziona.
authors.forename: A
authors.initials: A
authors.lastname: Fisher
authors.forename: E
authors.initials: E
authors.lastname: Heldman
authors.forename: D
authors.initials: D
authors.lastname: Gurwitz
authors.forename: R
authors.initials: R
authors.lastname: Haring
authors.forename: D
authors.initials: D
authors.lastname: Barak
authors.forename: H
authors.initials: H
authors.lastname: Meshulam
authors.forename: D
authors.initials: D
authors.lastname: Marciano
authors.forename: R
authors.initials: R
authors.lastname: Brandeis
authors.forename: Z
authors.initials: Z
authors.lastname: Pittel
authors.forename: M
authors.initials: M
authors.lastname: Segal
mesh_terms: D000109:Acetylcholine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000494:pharmacology*; D000544:Alzheimer Disease / Q000503:physiopathology; D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D015195:Drug Design; D006801:Humans; D010277:Parasympathomimetics / Q000138:chemical synthesis / Q000494:pharmacology*; D011976:Receptors, Muscarinic / Q000096:biosynthesis / Q000187:drug effects / Q000502:physiology*; D015398:Signal Transduction; D014162:Transfection
chemical_list: D010277:Parasympathomimetics; D011976:Receptors, Muscarinic; D000109:Acetylcholine