Cholinergic False Transmitters

Abstract

Publisher Summary A false neurotransmitter is a substance that is not normally present in a nerve ending, but which can accumulate in the sites that are usually occupied by the physiological neurotransmitter, and can be released by stimuli that normally release the physiological transmitter. This chapter discusses cholinergic false transmitters. All putative cholinergic false transmitters studied so far are formed from choline analogues. The criteria of presence, subcellular localization, and release have been demonstrated for acetyldiethylcholine, acetyltriethylcholine, acetylpyrrolidinecholine, and acetylhomocholine. The criteria of presence and release have been demonstrated for acetylmonethylcholine, and the criterion of presence for acetylsulfocholine. All of these presumed false transmitters are less active than is acetylcholine (ACh) at nicotinic and muscarinic receptor sites and all can be hydrolysed by acetylcholinesterase. Studies on the uptake, acetylation, storage, release and turnover of choline analogues and the false transmitters formed therefrom are likely to be of some use in clarifying presynaptic cholinergic mechanisms.