Functional nicotinic acetylcholine receptors in the neurons of rat intracardiac ganglia.

The alpha subunit composition of nicotinic acetylcholine receptors (nAChRs) expressed in the neurons of intracardiac ganglia of the rat was investigated using monoclonal and polyclonal antibodies against alpha3, alpha4, alpha5 and alpha7 nAChR subunits. The acetylcholine-induced membrane potentials in the neurons of the subepicardial plexus isolated from the left atrium of the heart were studied by intracellular recording performed in the presence of subunit-specific nAChR-blocking antibodies applied either separately or in various combinations. It was found that intracardiac ganglia neurons express alpha3alpha5; alpha7; alpha7(alpha5) and alpha4-containing nAChRs. The neurons were heterogeneous as to the nAChR subtypes expressed that possibly indicated their functional differences.