CHARACTERIZATION OF ETHYL (3-QUINUCLIDINYL) ACETATE (EQA) AS A LIGANDFOR ACETYLCHOLINE-RECEPTORS

Recent studies suggest that neuronal nicotinic acetylcholine receptors (nAChRs) may play a role in several CNS disorders and that subtype se lective nicotinic ligands may be useful in the treatment of these diso rders. Ethyl (3-quinuclidinyl)acetate (EQA) is a bulky, reverse-eater analog of ACh, that produces signs of cholinergic stimulation that may be nicotinic in origin. The objective of the present study was to fur ther evaluate EQA as a potential cholinergic ligand. Behavioral studie s, smooth muscle assays, and radioligand binding assays were performed on this novel ligand. The effects of EQA on blood pressure and acetyl cholinesterase activity were also evaluated. The results of the study suggest that EQA is an agonist at peripheral nicotinic acetylcholine r eceptors and may have antagonist properties at central nicotinic recep tors. (C) 1998 Elsevier Science Inc.